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Section BC 202: Definitions
Editor's note: this section has been amended by L.L. 2021/147, 12/11/2021, eff. 12/11/2024. For related unconsolidated provisions, see Appendix A at L.L. 2021/147. This section also has been amended by L.L. 2024/055, 4/6/2024. For related unconsolidated provisions and effective date provisions, see Appendix A at L.L. 2024/055.
24-HOUR BASIS. The actual time that a person is an occupant within a facility for the purpose of receiving care. It shall not include a facility that is open for 24 hours and is capable of providing care to someone visiting the facility during any segment of the 24 hours.
100-HOUR TRAINING PROGRAM. A program that (i) includes 100 or more hours of training in technical subjects relating to a construction trade, including an apprenticeship program registered with the New York State Department of Labor, (ii) is approved by OSHA, the United States Department of Labor, the New York State Department of Education or the New York State Department of Labor and (iii) provides training that the department determines is equivalent to or exceeds the training required to comply with Section 3321.
500-YEAR FLOOD ELEVATION. The elevation of the flood having a 0.2 percent chance of being equaled or exceeded in any given year, as specified on FEMA FIRM 360497 or FEMA FIS 360497.
AAC MASONRY. Masonry made of autoclaved aerated concrete (AAC) units, manufactured without internal reinforcement and bonded together using thin- or thick-bed mortar.
ACCESSIBLE. A site, building, facility or portion thereof that complies with Chapter 11.
ACCESSIBLE MEANS OF EGRESS. A continuous and unobstructed way of egress travel from any accessible point in a building or facility to a public way. Such way of egress travel may include an assisted rescue path.
ACCESSIBLE ROUTE. A continuous, unobstructed path that complies with Chapter 11.
ACCESSIBLE UNIT. A dwelling unit or sleeping unit that complies with this code and the provisions for Accessible units in ICC A117.1.
ACCREDITATION BODY. An approved, third-party organization that is independent of the grading and inspection agencies, and the lumber mills, and that initially accredits and subsequently monitors, on a continuing basis, the competency and performance of a grading or inspection agency related to carrying out specific tasks.
ACTIVELY PROCTORED ONLINE TRAINING. Online training that satisfies each of the following conditions:
   1.   The person responsible for conducting such training confirms the identification of the person taking such training in a manner established by the department.
   2.   While such training is being conducted, the site of such training is actively observed by or on behalf of the person responsible for conducting such training.
   3.   Such training complies with any other requirements the department establishes by rule.
ADHERED MASONRY VENEER. Veneer secured and supported through the adhesion of an approved bonding material applied to an approved backing.
ADJUSTMENT (SCAFFOLD). The calibration or modification of a scaffold, including any part or component, that does not meet the definition of installation, removal, repair, maintenance, or use, and does not constitute normal use or operation of the scaffold.
AEROSOL. A product that is dispensed from an aerosol container by a propellant, classified as follows:
   Level 1. Aerosol products with a total chemical heat of combustion that is greater than 0 and less than or equal to 8,600 British thermal units per pound (Btu/lb) (20 kJ/g).
   Level 2. Aerosol products with a total chemical heat of combustion that is greater than 8,600 Btu/lb (20 kJ/g), but less than or equal to 13,000 Btu/lb (30 kJ/g).
   Level 3. Aerosol products with a total chemical heat combustion that is greater than 13,000 Btu/lb (30 kJ/g).
AGGREGATE. In roofing, crushed stone, crushed slag or water-worn gravel used for surfacing for roof coverings.
AGRICULTURAL, BUILDING. A structure designed and constructed to house farm implements, hay, grain, poultry, livestock or other horticultural products. This structure shall not be a place of human habitation or a place of employment where agricultural products are processed, treated or packaged, nor shall it be a place used by the public.
AIR-INFLATED STRUCTURE. A structure that uses air-pressurized membrane beams, arches or other elements to enclose space. Occupants of such a structure do not occupy the pressurized area used to support the structure.
AIR-SUPPORTED STRUCTURE. A building wherein the shape of the structure is attained and maintained by elevated air pressure and occupants of the structure are within the elevated pressure area. Air-supported structures are of two basic types:
   Double skin. Similar to a single skin, but with an attached liner that is separated from the outer skin and provides an airspace which serves for insulation, acoustic, aesthetic or similar purposes.
   Single skin. Where there is only the single outer skin and the air pressure is directly against that skin.
AISLE. An unenclosed exit access component that defines and provides a path of egress travel.
AISLE ACCESSWAY. That portion of an exit that leads to an aisle.
ALARM NOTIFICATION APPLIANCE. A fire alarm system component such as a bell, horn, speaker, light or text display that provides audible, tactile or visible outputs, or any combination thereof.
ALARM SIGNAL. A signal indicating an emergency requiring immediate action, such as a signal indicative of fire.
ALARM VERIFICATION FEATURE. A feature of automatic fire detection and alarm systems to reduce unwanted alarms wherein smoke detectors report alarm conditions for a minimum period of time, or confirm alarm conditions within a given time period, after being automatically reset, in order to be accepted as a valid alarm-initiation signal.
ALLOWABLE STRESS DESIGN. A method of proportioning structural members, such that elastically computed stresses produced in the members by nominal loads do not exceed specified allowable stresses (also called "working stress design").
ALTERNATE LOAD PATH. A secondary or redundant load path capable of transferring the load from one structural element to other structural elements.
ALTERNATE LOAD PATH METHOD. A design approach that accounts for an extreme event by providing alternate load paths for elements that are no longer able to carry load. In an alternate load path design, key elements are considered notionally removed, one at a time, and the structure is designed to transfer the loads from the removed element to other structural elements, as required by Section 1617.
ALTERNATING TREAD DEVICE. A device that has a series of steps between 50 and 70 degrees (0.87 and 1.22 rad) from horizontal, usually attached to a center support rail in an alternating manner so that the user does not have both feet on the same level at the same time.
AMBULATORY CARE FACILITY. Buildings or portions thereof used to provide medical, surgical, psychiatric, nursing or similar care on a less than 24-hour basis to individuals who are rendered incapable of self-preservation by the services provided.
ANCHOR BUILDING. An exterior perimeter building of a group other than H having direct access to a covered mall building but having required means of egress independent of the mall.
ANCHORED MASONRY VENEER. Veneer secured and supported through the adhesion of an approved bonding material applied to an approved backing.
ANIMAL SERVICE FACILITY. The following facilities where animals are sheltered on a 24-hour basis: animal hospitals, kennels, pounds, veterinary clinics and pet shops.
ANNULAR SPACE. The opening around the penetrating item.
ANNUNCIATOR. A unit containing one or more indicator lamps, alphanumeric displays or other equivalent means in which each indication provides status information about a circuit, condition or location.
APARTMENT. A dwelling unit providing permanent provisions for both sanitation and kitchen facilities, occupied or arranged to be occupied by not more than one family maintaining a common household.
APARTMENT, STUDENT. An apartment occupied or arranged to be occupied by students enrolled at a single accredited college or university and maintaining a common household pursuant to a lease, sublease, or occupancy agreement directly with such college or university.
ARCHITECTURAL TERRA COTTA. Plain or ornamental hard-burned modified clay units, larger in size than brick, with glazed or unglazed ceramic finish.
AREA (Masonry).
   Gross cross-sectional. The area delineated by the out-to-out specified dimensions of masonry in the plane under consideration.
   Net cross-sectional. The area of masonry units, grout and mortar crossed by the plane under consideration based on out-to-out specified dimensions.
AREA, BUILDING. The area included within surrounding exterior walls (or exterior walls and firewalls) exclusive of vent shafts and courts. Areas of the building not provided with surrounding walls shall be included in the building area if such areas are included within the horizontal projection of the roof or floor above.
AREA OF RESCUE ASSISTANCE. An area where persons unable to use stairways can remain temporarily to await instructions or assistance during emergency evacuation.
AREA OF SPORT ACTIVITY. That portion of an indoor or outdoor space where the play or practice of a sport occurs.
AREAWAY. A space below grade adjacent to a building open to the outer air and enclosed by walls.
ARTICULATING BOOM CRANE. A crane whose boom consists of a series of folding, pin connected structural members, typically manipulated to extend or retract by power from hydraulic cylinders.
ASPECT RATIO. The height of any portion of a building divided by its least dimension at the elevation from which the height is being measured.
ASPHALT. A dark brown to black bitumen pitch that melts readily and which appears in nature in asphalt beds or is produced as a by-product of the petroleum industry.
ASPHALT CONCRETE or ASPHALT PAVING. A mixture of liquid asphalt and graded aggregate used as a paving material.
ASSEMBLY SPACE. Any part of a place of assembly, exclusive of the stage, that is occupied by numbers of persons during the major period of occupancy. Every tier of seating shall be considered a separate assembly space.
ASSISTED RESCUE PATH. A portion of the accessible means of egress which begins at the area of rescue assistance and terminates at the public way.
ATRIUM. An opening connecting two or more stories other than enclosed stairways, elevators, hoistways, escalators, plumbing, electrical, air-conditioning or any other vertical openings that are not required to be enclosed by other provisions of this code, which is closed at the top and not defined as a mall. Stories, as used in this definition, do not include balconies within assembly groups or mezzanines that comply with Section 505.
ATTIC. The space between the ceiling beams of the top story and the roof rafters.
AUDIBLE ALARM NOTIFICATION APPLIANCE. A notification appliance that alerts by the sense of hearing.
AUGERED-CAST-IN-PLACE PILES. Augered-cast-in-place piles are constructed by pumping grout into an augered hole during the withdrawal of the auger. The pile is reinforced with a single reinforcing bar, a reinforcing steel cage or a structural steel section.
AUTOCLAVED AERATED CONCRETE (AAC). Low-density cementitious product of calcium silicate hydrates, whose material specifications are defined in ASTM C 1386.
AUTOMATIC. As applied to fire protection devices, a device or system providing an emergency function without the necessity for human intervention and activated as a result of a predetermined temperature rise, rate of temperature rise and/or the presence of combustion products.
AUTOMATIC FIRE-EXTINGUISHING SYSTEM. An approved system of devices and equipment that automatically detects a fire and discharges an approved fire-extinguishing agent onto or in the area of a fire.
AUTOMATIC SMOKE DETECTION SYSTEM. A fire alarm system that has initiation devices that utilize smoke detectors for protection of an area such as a room or space with detectors to provide early warning of fire.
AUTOMATIC SPRINKLER SYSTEM. A fire suppression or control device that operates automatically when its heat-activated element is heated to its thermal rating or above, allowing water to discharge over a specified area.
AUTOMATIC WATER MIST SYSTEM. A system consisting of a water supply, a pressure source, and a distribution piping system with attached nozzles, which, at or above a minimum operating pressure defined by its listing, discharges water in fine droplets meeting the requirements of NFPA 750 for the purpose of the control, suppression or extinguishment of a fire. Such systems include wet-pipe, dry-pipe and pre-action types. The systems are designed as engineered, pre-engineered, local-application or total flooding systems.
AVERAGE AMBIENT SOUND LEVEL. The root mean square, A-weighted sound pressure level measured over a 24-hour period, or the time any person is present, whichever time period is less.
AWNING. An architectural projection that provides weather protection, identity or decoration and is wholly supported by the building to which it is attached. An awning is comprised of a lightweight frame structure over which a covering is attached.
AXIS OF ROTATION. The vertical axis around which the crane superstructure rotates.
AXLE. The shaft or spindle with which or about which a wheel rotates. On truck and wheel mounted cranes, it refers to a type of axle assembly including housing, gearing, differential, bearings, and mounting appurtenances.
A-ZONE. An area of special flood hazard without high-velocity wave action. When not shown on the FIRMs, the water surface elevation may be determined from available data by the registered design professional of record in accordance with Section G103.3. See also "Area of special flood hazard."
BACKING. The wall or surface to which the veneer is secured.
BALCONY, EXTERIOR. An exterior floor projecting from and supported by a structure without additional independent supports.
BALED COTTON. A natural seed fiber wrapped in and secured with industry accepted materials, typically consisting of burlap, woven polypropylene, polyethylene or cotton or sheet polyethylene, secured with wire or bands. The term baled cotton includes lint removed from the cottonseed (linters) and residual materials from the ginning process (motes).
BALED COTTON, DENSELY PACKED. Baled cotton with a packing density of not less than 22 pounds per cubic foot (360 kg/m 3 ). A bale of densely packed baled cotton typically measures 55 inches (1397 mm) in length, 21 inches (533.4 mm) in width, and 27.6 to 35.4 inches (701 to 899 mm) in height.
BALLAST. In roofing, ballast comes in the form of large stones or paver systems or light-weight interlocking paver systems and is used to provide uplift resistance to components of the roof assembly systems that are not adhered or mechanically attached to the roof deck.
BARRICADE (EXPLOSIVE). A structure or other artificial or natural barrier constructed in connection with the storage, handling and use of explosives that is designed to withstand the rapid release of energy in an explosion and provides a shield from the impact of such explosion. A straight line from the top of any sidewall of a building containing explosives to the eaveline of any magazine or other building or to a point 12 feet (3658 mm) above the center of a railway shall pass through such barrier.
   Artificial barricade. An artificial mound or revetment, including a barrier constructed of sandbags, with a minimum thickness of 3 feet (914 mm).
   Natural barricade. Terrain or other natural features of the ground.
BARRIER, TEMPORARY. An approved temporary fence, permanent fence, the wall of a permanent structure, any other structure, or any combination thereof that prevents access to the swimming pool by any person not engaged in the installation or construction of the swimming pool during its installation or construction.
BASE FLOOD. The flood having a 1-percent chance of being equaled or exceeded in any given year.
BASE FLOOD ELEVATION. The elevation of the base flood, including wave height, as specified on FEMA FIRMs 360497 or as determined in accordance with Section G103.3. In areas designated as ZONE AO, the base flood elevation shall be the elevation of the highest existing grade of the building's perimeter plus the depth number (in feet) specified on the flood hazard map.
BASE (MOUNTING). The traveling base on which the rotating superstructure of a crawler crane is mounted.
BASEMENT. A story partly below the grade plane and having less than one-half its clear height (measured from finished floor to finished ceiling) below the grade plan (see "Story" and "Story above grade plane"). A basement shall be considered a story above grade plane.
BASEMENT (FOR FLOOD ZONE PURPOSES). The portion of a building having its floor subgrade (below ground level) on all sides. This definition of "Basement" is limited in application to the provisions of Appendix G.
BEARER (PUTLOG). A horizontal transverse scaffold member (which may be supported by legs or runners) upon which the scaffold platform rests and joins scaffold uprights, posts, poles, and similar members.
BED JOINT. The horizontal layer of mortar on which a masonry unit is laid.
BIRD FRIENDLY MATERIAL. A material or assembly that has, or has been treated to have, a maximum threat factor of 25 in accordance with the American Bird Conservancy Bird Collision Deterrence Material Threat Factor Reference Standard or with the American Bird Conservancy Bird-friendly Materials Evaluation Program at Carnegie Museum's Avian Research Center test protocol.
BIRD HAZARD INSTALLATIONS. Monolithic glazing installations that provide a clear line of sight on the exterior of buildings, including, but not limited to, glass awnings, glass handrails and guards, glass wind break panels, or glass acoustic barriers.
BLEACHERS. Tiered seating supported on a dedicated structural system and two or more rows high and is not a building element (see "Grandstand").
BOARDER (ROOMER, LODGER). A person who pays a consideration for living within the household and does not occupy such space as an incident of employment.
BOILING POINT. The temperature at which the vapor pressure of a liquid equals the atmospheric pressure of 14.7 pounds per square inch (psia) (101 kPa) or 760 mm of mercury. Where an accurate boiling point is unavailable for the material in question, or for mixtures which do not have a constant boiling point, for the purposes of this classification, the 20-percent evaporated point of a distillation performed in accordance with ASTM D 86 shall be used as the boiling point of the liquid.
BOOM (CRANE OR DERRICK). A section or strut, of which the heel (lower end) is affixed to a base, carriage, or support, and whose upper end supports a cable and sheaves where the load is lifted by means of rope and a hook.
BOOM POINT. The outer extremity of the crane boom, containing the hoist sheave assembly.
BRACED WALL LINE. A straight line through the building plan that represents a location of the lateral resistance provided by wall bracing.
BRACED WALL PANEL. A full-height section of wall constructed to resist in-plane shear loads through interaction of framing members, sheathing material and anchors. The panel's length meets the requirements of its particular bracing method and contributes toward the total amount of bracing required along its braced wall line.
BRAKE. A device used for retarding or stopping motion.
BREAKAWAY WALL. An open lattice wall subject to flooding that is not required to provide structural support to a building or other structure and that is designed and constructed such that, under base flood or lesser flood conditions, it will collapse under specific lateral-loading forces in such a way that (i) it allows the free passage of floodwaters, and (ii) it does not damage the structure or the supporting foundation system.
BREAKOUT. For revolving doors, a process whereby wings or door panels can be pushed open manually for means of egress travel.
BRICK.
   Calcium silicate (sand lime brick). A pressed and subsequently autoclaved unit that consists of sand and lime, with or without the inclusion of other materials.
   Clay or shale. A solid or hollow masonry unit made of clay or shale, usually formed into a rectangular prism, then burned or fired in a kiln; brick is a ceramic product.
   Concrete. A concrete masonry unit made from portland cement, water, and suitable aggregates, with or without the inclusion of other materials.
BUCKET HOIST. A power or manually operated bucket that (i) is temporarily installed at a construction or demolition site, (ii) moves vertically on guide members to raise or lower material, and (iii) is controlled from a point outside the conveyance.
BUILDING ELEMENT. A fundamental component of building construction, listed in Table 601, which may or may not be of fire-resistance-rated construction and is constructed of materials based on the building type of construction.
BUILDING, ENCLOSED. A building that does not comply with the requirements for open or partially enclosed buildings.
BUILDING LINE. The line established by law, beyond which a building shall not extend, except as specifically provided by law.
BUILDING, LOW-RISE. Enclosed or partially enclosed buildings that comply with the following conditions:
   1.   Mean roof height, h, less than or equal to 60 feet (18 288 mm).
   2.   Mean roof height, h, does not exceed least horizontal dimension.
BUILDING, OPEN. A building having each wall at least 80 percent open. This condition is expressed for each wall by the equation:
Ao   0.8Ag      (Equation 2-1)
where:
   Ao = Total area of openings in a wall that receives positive external pressure, in square feet (m 2 ).
   Ag =   The gross area of that wall in which Ao is identified, in square feet (m 2 ).
BUILDING, PARTIALLY ENCLOSED. A building that complies with both of the following conditions:
   1.   The total area of openings in a wall that receives positive external pressure exceeds the sum of the areas of openings in the balance of the building envelope (walls and roof) by more than 10 percent; and
   2.   The total area of openings in a wall that receives positive external pressure exceeds 4 square feet (0.37 m 2 ) or 1 percent of the area of that wall, whichever is smaller, and the percentage of openings in the balance of the building envelope does not exceed 20 percent. These conditions are expressed by the following equations:
   Ao > 1.10Aoi      (Equation 2-2)
   Ao > 4 square feet (0.37 m 2 ) or > 0.01Ag ,whichever is smaller,and Aoi / Agi   0.20      (Equation 2-3)
   where:
      Ao, Ag are as defined for an open building.
      Aoi = The sum of the areas of openings in the building envelope (walls and roof) not including Ao, in square feet (m 2).
      Agi = The sum of the gross surface areas of the building envelope (walls and roof) not including Ag, in square feet (m 2).
BUILDING, SIMPLE DIAPHRAGM. A building in which wind loads are transmitted through floor and roof diaphragms to the vertical lateral-force-resisting systems.
BUILDING-INTEGRATED PHOTOVOLTAIC (BIPV) PRODUCT. A building product that incorporates photovoltaic modules and functions as a component of the building envelope.
BUILDINGS AND OTHER STRUCTURES, FLEXIBLE. Buildings and other structures that have a fundamental natural frequency less than 1 Hz.
BUILT-UP ROOF COVERING. Two or more layers of felt cemented together and surfaced with a cap sheet, mineral aggregate, smooth coating or similar surfacing material.
BULKHEAD. An enclosed rooftop structure enclosing a shaft, stairway, tank or service equipment, or other space not designed or used for human occupancy.
CABARET. Any room, place or space in which any musical entertainment, singing, dancing or other similar amusement is permitted in connection with an eating and drinking establishment.
CABLE-RESTRAINED, AIR-SUPPORTED STRUCTURE. A structure in which the uplift is resisted by cables or webbings that are anchored to either foundations or dead men. Reinforcing cable or webbing is attached by various methods to the membrane or is an integral part of the membrane. This is not a cable-supported structure.
CABLEWAY. A device used for hoisting, lowering, and transporting loads within a prescribed path, longitudinally and laterally. The load block (upper) travels on a rope catenary system having span ends that are supported on fixed or movable towers (masts) or other elevated supports.
CAISSON PILES. Steel cased piles constructed by advancing a steel shell seated into rock and drilling of an uncased socket within the rock. The shell and socket are filled with a steel core section or steel reinforcing, and concrete or grout.
CANOPY. A permanent structure or architectural projection of rigid construction over which a covering is attached that provides weather protection, identity or decoration, which shall be structurally independent or supported by attachment to a building on one end and by not fewer than one stanchion at the outer end.
CARBON DIOXIDE EXTINGUISHING SYSTEMS. A system supplying carbon dioxide (CO 2 ) from a pressurized vessel through fixed pipes and nozzles. The system includes a manual- or automatic-actuating mechanism.
CARBON MONOXIDE ALARM. A listed single- or multiple-station alarm responsive to carbon monoxide.
CARBON MONOXIDE DETECTOR. A listed device that senses carbon monoxide.
CARBON MONOXIDE-PRODUCING EQUIPMENT. Any furnace, boiler, water heater, fireplace, cooking appliance, gas clothes dryer, apparatus, appliance or device that burns coal, kerosene, oil, wood, fuel gases and other petroleum products including, but not limited to, methane, natural gas, liquefied natural gas and manufactured fuel gases.
CARE SUITE. In Group I-2 occupancies, a group of treatment rooms, care recipient sleeping rooms and the support rooms or spaces and circulation space within the suite where staff are in attendance for supervision of all care recipients within the suite, and the suite is in compliance with the requirements of Section 407.4.4.
CARPORT. A structure or portion of a structure, accessory to a Group R-2 or R-3 occupancy, open on at least two sides and unenclosed for at least 50 percent of perimeter, used for the parking or storage of passenger motor vehicles. Such facility shall not exceed 650 square feet (60.45 m 2 ) in area and one story in height.
CAST STONE. A building stone manufactured from portland cement concrete precast and used as a trim, veneer or facing on or in buildings or structures.
CEILING LIMIT. The maximum concentration of an air-borne contaminant to which one may be exposed. The ceiling limits utilized are those published in DOL 29 CFR Part 1910.1000. The ceiling Recommended Exposure Limit (REL-C) concentrations published by the U.S. National Institute for Occupational Safety and Health (NIOSH), Threshold Limit Value – Ceiling (TLV-C) concentrations published by the American Conference of Governmental Industrial Hygienists (ACGIH), Ceiling Workplace Environmental Exposure Level (WEEL-Ceiling) Guides published by the American Industrial Hygiene Association (AIHA), and other approved, consistent measures are allowed as surrogates for hazardous substances not listed in DOL 29 CFR Part 1910.1000.
CEILING RADIATION DAMPER. See "Dampers, Types of."
CELL. See Section 408.1.1.
CELL. As used in Chapter 21, a void space having a gross cross-sectional area greater than 1 1/2 square inches (967 mm 2 ).
CELL TIER. See Section 408.1.1.
CELLAR. That portion of a building that is partly or wholly underground, and having one-half or more of its clear height (measured from finished floor to finished ceiling) below the grade plane. Cellars shall not be counted as stories in measuring the height of the buildings.
CEMENT BOARD. A fiber reinforced cementitious panel most commonly used under flooring or as a tile backing board. Cement board shall include discrete nonasbestos fiber-cement interior substrate sheets or nonasbestos fiber-mat reinforced cement substrate sheets.
CEMENT PLASTER. A mixture of portland or blended cement, portland cement or blended cement and hydrated lime, masonry cement or plastic cement and aggregate and other approved materials as specified in this code.
CEMENTED SOIL. Soil in which the particles are held together by a chemical agent, such as calcium carbonate, such that a hand-size sample cannot be crushed into powder or individual soil particles by finger pressure.
CERAMIC FIBER BLANKET. A high-temperature mineral wool insulation material made of alumina-silica ceramic or calcium magnesium silicate soluble fibers and weighing 4 to 10 pounds per square cubic foot (pcf) (64 to 160 kg/m 3 ).
CERTIFICATE OF APPROVAL. A certificate issued by the department upon review and approval of the engineering and testing of a specific make and model of hoisting equipment to ensure compliance with the applicable provisions of this code.
CERTIFICATE OF OPERATION. A certificate issued by the department upon satisfactory inspection of a specific piece of hoisting equipment to ensure that the equipment is in compliance with this code.
CERTIFICATE OF ON-SITE INSPECTION. A certificate issued by the department based on a site-specific inspection of the placement and founding of hoisting equipment.
CHILD CARE FACILITIES. See Section 308.2.1.
CHIMNEY. A primarily vertical structure containing one or more flues used to remove hot gases from burning fuel, refuse, or from industrial processes to the outdoor atmosphere.
   Factory-built chimney. A listed and labeled chimney composed of factory-made components, assembled in the field in accordance with manufacturer's instructions and the conditions of the listing.
   Masonry chimney. A field-constructed chimney composed of solid masonry units, bricks, stones, or concrete.
   Metal chimney. A field-constructed chimney of metal.
CHIMNEY TYPES.
   High-heat appliance type. An approved chimney for removing the products of combustion from fuel-burning, high-heat appliances producing combustion gases in excess of 2,000°F (1093°C) measured at the appliance flue outlet (see Section 2113.11.3).
   Low-heat appliance type. An approved chimney for removing the products of combustion from fuel-burning, low-heat appliances producing combustion gases not in excess of 1,000°F (538°C) under normal operating conditions, but capable of producing combustion gases of 1,400°F (760°C) during intermittent forces firing for periods up to 1 hour. Temperatures shall be measured at the appliance flue outlet.
   Medium-heat appliance type. An approved chimney for removing the products of combustion from fuel-burning, medium-heat appliances producing combustion gases between 1,000°F (538°C) and 2,000°F (1093°C) measured at the appliance flue outlet (see Section 2113.11.2).
CIRCULATION PATH. An exterior or interior way of passage from one place to another for pedestrian travel, including that within accessible spaces.
CLAMSHELL. A shovel bucket with two jaws that clamp together by their own weight when it is lifted by a closing line.
CLEAN AGENT. Electrically nonconducting, volatile or gaseous fire extinguishant that does not leave a residue upon evaporation.
CLIMBER CRANE. A tower crane that can be raised to a new working height, either by adding tower sections to the top of the crane (top climbing), or by a system in which the entire crane is raised inside the structure (inside climbing).
CLINIC, OUTPATIENT. Buildings or portions thereof used to provide medical care on less than a 24-hour basis to persons who are not rendered incapable of self-preservation by the services provided.
CLOSED SYSTEM. The use of any compressed gas and the use of a solid or liquid hazardous material in equipment or a vessel or system that remains closed during normal operations, such that vapors emitted during the operation of such equipment, vessel or system are not liberated outside of the equipment, vessel or system and the gas or hazardous material is not exposed to the atmosphere during such operation. Examples of closed systems include hazardous materials conveyed through a piping system into closed equipment of a closed vessel or system.
CLOSED-CIRCUIT TELEPHONE. A telephone with a dedicated line such as a house phone, courtesy phone or phone that must be used to gain entrance to a facility.
COASTAL A-ZONE. An area within a special flood hazard area, shown on FEMA FIRMs 360497 as an area bounded by a "Limit of Moderate Wave Action", landward of a V-Zone or landward of an open coast without mapped V-Zones. In a Coastal A-Zone, the principal source of flooding must be astronomical tides, storm surges, seiches, or tsunamis, and not riverine flooding. During the base flood conditions, the potential for breaking wave heights must be greater than or equal to 1 foot, 6 inches (457 mm). In no case shall an area of special flood hazard be deemed a coastal A-Zone unless and until it has been identified as such on the adopted FEMA FIRMs 360497.
COASTAL HIGH HAZARD AREA. Area within the area of special flood hazard extending from offshore to the inland limit of a primary dune along an open coast and any other area that is subject to high-velocity wave action from storms and shown on FEMA FIRMs 360497 as velocity Zone V, VO, VE or V1-30.
COHESIVE SOIL. Clay (fine grained soil), or soil with a high clay content, which has cohesive strength. Cohesive soil does not crumble, can be excavated with vertical side slopes, and is plastic when moist. Cohesive soil is hard to break up when dry, and exhibits significant cohesion when submerged. Cohesive soils include clayey silt, sandy clay, silty clay, clay and organic clay.
COLLAPSE (STRUCTURAL). Failure of a structural element to the extent that it can no longer support any load.
COLLAR JOINT. Vertical longitudinal space between wythes of masonry or between masonry wythe and backup construction that is permitted to be filled with mortar or grout.
COLLECTING SAFE AREA. See Section 1002.1.2.
COLLECTOR. A horizontal diaphragm element parallel and in line with the applied force that collects and transfers diaphragm shear forces to the vertical elements of the lateral-force-resisting system or distributes forces within the diaphragm or both.
COMBINATION FIRE/SMOKE DAMPER. See "Dampers, Types of."
COMBINATION SIGN. A sign incorporating any combination of the features of pole, projecting and roof signs.
COMBINED HEAT AND POWER SYSTEMS. Equipment that simultaneously produces electricity and heat from a single fuel source.
COMBUSTIBLE DUST. Finely divided solid material that is 420 microns or less in diameter, will pass through a U.S. standard No. 40 sieve and, when dispersed in air in sufficient concentrations, can be ignited by a flame, spark or other source of ignition.
COMBUSTIBLE FIBERS. Readily ignitable and free-burning materials in fibrous or shredded form, such as cocoa fiber, cotton, excelsior, hay, hemp, henequen, istle, jute, kapok, oakum, sisal, Spanish moss, straw, tow, wastepaper or other natural or synthetic fibers that possess similar qualities, but excluding densely packed baled cotton.
   Exception: Moss used for medicinal purposes.
COMBUSTIBLE LIQUID. For the purposes of transportation, a combustible liquid as defined in the regulations of the United States of Transportation, as set forth in 49 CFR 173.120. For all other purposes, a liquid, other than a compressed gas or cryogenic fluid, having a closed cup flash point at or above 100°F (38°C) classified as follows:
   Class II. Liquids having a closed cup flash point at or above 100°F (38°C) and below 140°F (60°C).
   Class IIIA. Liquids having a closed cup flash point at or above 140°F (60°C) and below 200°F (93°C).
   Class IIIB. Liquids having a closed cup flash point at or above 200°F (93°C).
COMMERCIAL COOKING SYSTEM. A system consisting of commercial cooking equipment, exhaust hood, filters, exhaust duct system, fire suppression system and other related appurtenances designed to capture grease-laden cooking vapors and exhaust them safely to the outdoors.
COMMERCIAL MOTOR VEHICLE. A motor vehicle used to transport passengers or goods where the motor vehicle:
   1.   Has a gross vehicle weight rating of 10,000 pounds (4540 kg) or more; or
   2.   Is designed to transport 16 or more passengers, including the driver.
COMMERCIAL TRUCK MOUNTED CRANE (BOOM TRUCK). A mobile crane consisting of a rotating superstructure (center post or turntable), boom, operating machinery, and one or more operator's stations mounted on a frame attached to a commercial truck chassis.
COMMON PATH OF EGRESS TRAVEL. That portion of exit access that the occupants are required to traverse before two separate and distinct paths of egress travel to two exits are available. Paths that merge are common paths of travel. Common paths of egress travel shall be included within the permitted travel distance.
COMMON USE. Interior or exterior circulation paths, rooms, spaces or elements that are made available for the shared use of two or more people but are not for public use.
COMPACTED CONCRETE PILES. Compacted concrete piles are constructed by filling a driven casing with low-strength concrete and compacting the concrete as the casing is withdrawn.
COMPETENT PERSON. One who is capable of identifying existing and predictable hazards in the surroundings or conditions that are unsanitary, hazardous or dangerous, and who has authorization to take prompt corrective measures to eliminate such hazards.
COMPLETED STEEL FLOOR. Any floor, in a building whose primary structural system consists of structural steel, where the structural floor system, including the final walkable structural surface, has been installed and has achieved its required strength for construction loading.
COMPONENTS AND CLADDING. Elements of the building envelope that do not qualify as part of the main wind force-resisting system.
COMPOSITE PILES. Composite piles consist of two or more approved pile types joined together.
COMPRESSED GAS. A material, or mixture of materials that:
   1.   Is a gas at 68°F (20°C) or less at 14.7 psia (101 kPa) of pressure; and
   2.   Has a boiling point of 68°F (20°C) or less at 14.7 psia (101 kPa) that is either liquefied, nonliquefied or in solution at that temperature and pressure, except those gases which have no other health- or physical-hazard properties are not considered to be compressed until the pressure in the packaging exceeds 41 psia (282 kPa) at 68°F (20°C).
The states of compressed gases are categorized as follows:
   Nonliquefied compressed gases. Gases, other than those in solution, which are in packaging under the charged pressure and are entirely gaseous at a temperature of 68°F (20°C).
   Liquefied compressed gases. Gases that, in a packaging under the charged pressure, are partially liquid at a temperature of 68°F (20°C).
   Compressed gases in solution. Nonliquefied gases that are dissolved in a solvent.
   Compressed gas mixtures. A mixture of two or more compressed gases contained in a single packaging, the hazard properties of which are represented by the properties of the mixture as a whole.
CONCEALED SPACES. Enclosed spaces within partitions, walls, floors, roofs, stairs, furring, pipe chases and column enclosures and other similar spaces.
CONCRETE.
   Carbonate aggregate. Concrete made with aggregates consisting mainly of calcium or magnesium carbonate, such as limestone or dolomite, and containing 40 percent or less quartz, chert, or flint.
   Cellular. A lightweight insulating concrete made by mixing a preformed foam with portland cement slurry and having a dry unit weight of approximately 30 pcf (480 kg/m 3 ).
   Lightweight aggregate. Concrete made with aggregates of expanded clay, shale, slag or slate or sintered fly ash or any natural lightweight aggregate meeting ASTM C 330 and possessing equivalent fire-resistance properties and weighing 85 to 115 pcf (1360 to 1840 kg/m 3 ).
   Perlite. A lightweight insulating concrete having a dry unit weight of approximately 30 pcf (480 kg/m 3 ) made with perlite concrete aggregate. Perlite aggregate is produced from a volcanic rock that, when heated, expands to form a glass-like material of cellular structure.
   Sand-lightweight. Concrete made with a combination of expanded clay, shale, slag, slate, sintered fly ash, or any natural lightweight aggregate meeting ASTM C 330 and possessing equivalent fire-resistance properties and natural sand. Its unit weight is generally between 105 and 120 pcf (1680 and 1920 kg/m 3 ).
   Siliceous aggregate. Concrete made with normal-weight aggregates consisting mainly of silica or compounds other than calcium or magnesium carbonate, which contains more than 40-percent quartz, chert, or flint.
   Vermiculite. A lightweight insulating concrete made with vermiculite concrete aggregate that is laminated micaceous material produced by expanding the ore at high temperatures. When added to a portland cement slurry the resulting concrete has a dry unit weight of approximately 30 pcf (480 kg/m 3 ).
CONCRETE-FILLED STEEL PIPE AND TUBE PILES. Concrete-filled steel pipe and tube piles are constructed by driving a steel pipe or tube section into the soil and filling the pipe or tube section with concrete. The steel pipe or tube section is left in place during and after the deposition of the concrete. For the purposes of this code, these piles shall be considered driven piles.
CONCRETE WASHOUT WATER. Wastewater from the rinsing of equipment used to mix, transport, convey, and/or place concrete. Such equipment shall include, but not be limited to, concrete buckets, concrete hose lines and pumps, boots, shovels, finishing tools, wheelbarrows, motorized concrete carts, concrete pour funnels and the chute of concrete mixer trucks.
   Exceptions:
      1.   This term shall not include wastewater from the rinsing of equipment involved in the preparation, conveyance or application of concrete that is:
         1.1.   mixed on site if the total quantity of concrete is less than or equal to one and one half cubic yards (1.146 m 3 ), or
         1.2.   from bagged ready mix if the total quantity of concrete is less than or equal to sixty (60) eighty pound (36.287 kg) bags, or eighty (80) sixty pound (27.215 kg) bags, or the equivalent.
      2.   This term shall not include wastewater from the rinsing of the wheels, undercarriage or chassis of concrete mixer trucks.
CONGREGATE LIVING UNIT. A dwelling unit, comprised of one or more habitable rooms separated by nonrated partitions, occupied or arranged to be occupied by more than one family or by persons who are not maintaining a common household. Creation of or conversion to such unit shall be subject to Section 27-2077 of the New York City Housing Maintenance Code.
CONSTANTLY ATTENDED LOCATION. A designated location at a facility staffed by trained personnel on a continuous basis where alarm or supervisory signals are monitored and facilities are provided for notification of the Fire Department of other emergency services.
CONSTRUCTION. The excavation, erection, alteration, and repair of buildings or any component parts, including all operations incidental thereto.
CONTAINER GARDEN. A plant or plants maintained in a pot or planters located on a roof, terrace, or other horizontal exterior area.
CONTINUOUS GAS DETECTION SYSTEM. A gas detection system where the analytical instrument is maintained in continuous operation and sampling is performed without interruption. Analysis is allowed to be performed on a cyclical basis at intervals not to exceed 30 minutes.
CONTROL AREA. Spaces within a building where quantities of hazardous materials not exceeding the maximum allowable quantities per control area are stored, handled, or used, including any dispensing. See also definition of "Outdoor control area" in the New York City Fire Code.
CONTROLLED LOW-STRENGTH MATERIAL. A self-compacted, cementitious material used primarily as a backfill in place of compacted fill.
CONVENTIONAL LIGHT-FRAME CONSTRUCTION. A type of construction whose primary structural elements are formed by a system of repetitive wood-framing members. See Section 2308 for conventional light-frame construction provisions.
CORNER SCAFFOLD (ANGLE SCAFFOLD). A suspended scaffold consisting of an assembly of two or more platforms connected nonlinearly and designed and manufactured to fit around a corner or a projecting part of a building.
CORRIDOR. An enclosed exit access component that defines and provides a path of egress travel to an exit. Corridors shall be either interior or public.
   Corridor, interior. A corridor that serves only one tenant. In Group E occupancies, corridors serving only one institution shall be deemed as serving a single tenant.
   Corridor, public. A corridor that serves more than one tenant.
CORROSIVE MATERIAL. A material that causes full thickness destruction of human skin at the site of contact within a specified period of time when tested by methods set forth in DOTn regulations 49 CFR 173.136 and 173.137, or a liquid that has a severe corrosion rate on steel or aluminum based on the criteria set forth in DOTn regulations 49 CFR 173.173(c)(2).
CORROSION RESISTANCE. The ability of a material to withstand deterioration of its surface or its properties when exposed to its environment.
COUNTERWEIGHT. Weight used to supplement the weight of the machine in order to provide stability for lifting loads.
COURT. An open, uncovered space, unobstructed to the sky, bounded on three or more sides by exterior building walls or other enclosing devices.
COVERED DEVELOPMENT PROJECT. See Section 28-104.11.1 of the Administrative Code.
COVERED MALL BUILDING . A single building enclosing a number of tenants and occupants such as retail stores, drinking and dining establishments, entertainment and amusement facilities, passenger transportation terminals, offices, and other similar uses wherein two or more tenants have a main entrance into one or more malls. For the purpose of this chapter, anchor buildings shall not be considered as part of the covered mall building. The term "Covered Mall Building" shall include open mall buildings as defined below.
   Mall. A roofed or covered common pedestrian area within a covered mall building that serves as access for two or more tenants and not to exceed three levels that are open to each other. The term "mall" shall include open malls as defined below.
   Open mall. An unroofed common pedestrian way serving a number of tenants not exceeding three levels. Circulation at levels above grade shall be permitted to include open exterior balconies leading to exits discharging at grade.
   Open mall building. Several structures housing a number of tenants, such as retail stores, drinking and dining establishments, entertainment and amusement facilities, offices and other similar uses, wherein two or more tenants have a main entrance into one or more open malls. For the purposes of Chapter 4, anchor buildings are not considered as part of the open mall building.
CRANE. A power operated machine that can (i) hoist, lower, and horizontally move a suspended load, or (ii) lift, lower, and horizontally swing a load utilizing a boom, jib, arm, or similar member, regardless of whether it is fixed, folds, telescopes, or articulates. The definition of crane includes, but is not limited to, an articulating boom crane, mobile crane, tower crane, dedicated pile driver, and rotating telehandler. The definition of crane shall not include a derrick or cableway.
CRAWLER CRANE. A mobile crane consisting of a rotating superstructure with a power plant, operating machinery, and boom, mounted on a base and equipped with crawler treads for travel.
CRIPPLE WALL. A framed stud wall extending from the top of the foundation to the underside of floor framing for the lowest occupied floor level.
CRITICAL PICK. The attachment and detachment of loads from the hook of hoisting equipment used to hoist or lower loads on the outside of a building that involves one or more of the following:
   1.   An article that is at or above 95 percent of approved rated capacity of the hoisting equipment or rigging equipment;
   2.   An article that is asymmetrical and is not provided with lifting connections by the manufacturer or fabricator;
   3.   An article that has a wind sail area exceeding 500 square feet (46 m 2 );
   4.   A pick that may present an added risk because of clearance, drift, or other interference;
   5.   An article that is fragile or of thin shell construction and is not provided with standard rigging ears;
   6.   A pick that requires multiple power-operated hoisting equipment (tandem pick); or
   7.   A pick that require out of the ordinary rigging equipment, methods, or setup.
CROSS AISLE. An unenclosed exit access component in a place of assembly usually parallel to rows of seats, connecting aisles or connecting an aisle and an exit. For the purposes of Chapter 10, a cross aisle is not an aisle.
CROSS-LAMINATED TIMBER (CLT). A prefabricated engineered wood product made of at least three orthogonal layers of graded sawn lumber or structural composite lumber (SCL) that are laminated by gluing with structural adhesives.
CRYOGENIC FLUID. A liquid having a boiling point lower than -130°F (-89.9°C) at 14.7 pounds per square inch absolute (psia) (an absolute pressure of 101.3 kPa).
CURB LEVEL. As defined in the New York City Zoning Resolution.
CURB LINE. The line coincident with the face of the street curb adjacent to the roadway.
CURTAIN WALL. A curtain wall or panel wall system is a nonload-bearing building wall, in skeleton frame construction, attached and supported to the structure at every floor or other periodic locations. Assemblies may include glass, metal, precast concrete or masonry elements arranged so as not to exert common action under load and to move independently of each other and the supporting structure.
CUSTODIAL CARE FACILITY. A building or part thereof occupied by persons, on less than a 24-hour basis and not overnight, who because of age, disability or other reasons, receive personal care services by individuals other than parents or guardians, relatives by blood, marriage, domestic partnership, or adoption, in a place other than the home of the person cared for.
DALLE GLASS. A decorative composite glazing material made of individual pieces of glass that are embedded in a cast matrix of concrete or epoxy.
DAMPERS, TYPES OF.
   Ceiling radiation damper. A listed device, installed in a ceiling membrane of a fire-resistance-rated floor/ceiling or roof/ceiling assembly to limit automatically the radiative heat transfer through an air inlet/outlet opening. Ceiling radiation dampers include air terminal units, ceiling dampers and ceiling air diffusers.
   Combination fire/smoke damper. A listed device, installed in ducts and air transfer openings designed to close automatically upon the detection of heat and resist the passage of flame and smoke. The device is installed to operate automatically controlled by a smoke detection system, and where required, is capable of being positioned from a fire command center.
   Fire damper. A listed device, installed in ducts and air transfer openings designed to close automatically upon detection of heat and restrict the passage of flame. Fire dampers are classified for use in either static systems that will automatically shut down in the event of a fire, or in dynamic systems that continues to operate during a fire. A dynamic fire damper is tested and rated for closure under elevated temperature airflow.
   Smoke damper. A listed device, installed in ducts and air transfer openings designed to resist the passage of air and smoke. The device is installed to operate automatically, controlled by a smoke detection system, and where required, is capable of being positioned from a fire command center.
DAMPPROOFING. Dampproofing is a protective measure applied to building foundation walls and slabs to prevent moisture from passing into interior spaces.
DAY BOX. A portable magazine designed to hold explosive materials constructed in accordance with the requirements for a Type 3 magazine as defined and classified in the New York City Fire Code.
DEAD END. A portion of a corridor in which the travel to an exit is in one direction only.
DEAD LOAD. The weight of materials of construction incorporated into the building, including but not limited to walls, floors, roofs, ceilings, stairways, built-in partitions, finishes, cladding and other similarly incorporated architectural and structural items, and the weight of fixed service equipment, such as cranes, plumbing stacks and risers, electrical feeders, heating, ventilating and air-conditioning systems and automatic sprinkler systems.
DEBRIS. Rubbish, waste, discarded material, or the remains of something broken down, demolished, or destroyed.
DEBRIS NET or NETTING. A netting of a fine mesh of a size and strength sufficient to catch debris, such as falling tools and materials.
DECK. An exterior floor supported on at least two opposing sides by an adjacent structure and/or posts, piers, or other independent supports.
DECORATIVE GLASS. A carved, leaded or Dalle glass or glazing material whose purpose is decorative or artistic, not functional; whose coloring, texture or other design qualities or components cannot be removed without destroying the glazing material and whose surface, or assembly into which it is incorporated, is divided into segments.
DECORATIVE MATERIALS. All materials applied over the building interior finish for decorative, acoustical or other effect (such as curtains, draperies, fabrics, streamers and surface coverings), and all other materials utilized for decorative effect (such as batting, cloth, cotton, hay, stalks, straw, vines, leaves, trees, moss and similar items), including foam plastics and materials containing foam plastics. Decorative materials do not include floor coverings, ordinary window shades, interior finish and materials 0.025 inch (0.64 mm) or less in thickness applied directly to and adhering tightly to a substrate.
DECORATIVE SHROUD. A listed partial combustible enclosure for aesthetic purposes that is installed at the termination of a venting system that surrounds or conceals the chimney or vent cap.
DEDICATED PILE DRIVER. A power operated machine that is designed primarily to drive, hammer, press, or vibrate piles into the earth ("pile drive"). These machines typically have the ability to both hoist the material that will be pile driven and to pile drive that material.
DEEP FOUNDATIONS. Deep foundations are comprised of concrete, grout, wood or steel structural elements either driven, drilled or jacked into the ground or cast in place. Deep foundations are relatively slender in comparison to their length, with lengths exceeding 12 times the least horizontal dimension. Deep foundations derive their load-carrying capacity through skin friction, end bearing, or a combination thereof.
DEFLAGRATION. An exothermic reaction, such as the extremely rapid oxidation of a flammable dust or vapor in air, in which the reaction progresses through the unburned material at a rate less than the velocity of sound. A deflagration can have an explosive effect.
DELUGE SPRINKLER SYSTEM. A sprinkler system employing open sprinklers attached to a piping system connected to a water supply through a valve that is opened by the operation of a detection system installed in the same areas as the sprinklers. When this valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.
DEMOLITION. Full or partial demolition.
   Full demolition. The dismantling, razing, or removal of all of a building or structure, including all operations incidental thereto.
   Partial demolition. The dismantling, razing, or removal of structural members, floors, interior bearing walls, and/or exterior walls or portions thereof, including all operations incidental thereto.
DERRICK. An apparatus consisting of a mast or equivalent member held at the end by guys or braces, with or without a boom, for use with a hoisting mechanism and operating ropes, for lifting or lowering a load and moving it horizontally.
DESIGN EARTHQUAKE GROUND MOTION. The earthquake ground motion that buildings and structures are specifically proportioned to resist in Section 1613.
DESIGN FLOOD ELEVATION. The applicable elevation specified in ASCE 24, Tables 2-1, 4-1, 5-1, 6-1, or 7-1, depending on the flood design class designated in ASCE 24, Table 1-1.
DESIGN STRENGTH. The product of the nominal strength and a resistance factor (or strength reduction factor).
DETACHED BUILDING. A separate single-story building, without a basement or crawl space, used for the storage, handling or use of hazardous materials and located an approved distance from other buildings and structures.
DETECTABLE WARNING. A standardized surface feature built in or applied to walking surfaces or other elements to warn a person who is blind or has low vision of hazards on a circulation path.
DETECTOR, HEAT. A fire detector that senses heateither abnormally high temperature or rate of rise, or both.
DETONATION. An exothermic reaction with explosive effect that utilizes shock compression as the principal heating mechanism and generates a shock wave in the material that establishes and maintains a reaction that progresses through the material at a rate greater than the velocity of sound.
DETOXIFICATION FACILITIES. See Section 308.2.1.
DEVELOPMENT. See Section G201.1.2.
DEWATERING. The removal of surface or ground water from a site by pumping or evaporation.
DIAPHRAGM. A horizontal or sloped system acting to transmit lateral forces to vertical elements of the lateral force-resisting system. When the term "diaphragm" is used, it shall include horizontal bracing systems.
   Diaphragm, blocked. In light-frame construction, a diaphragm in which all sheathing edges not occurring on a framing member are supported on and fastened to blocking.
   Diaphragm boundary. In light-frame construction, a location where shear is transferred into or out of the diaphragm sheathing. Transfer is either to a boundary element or to another force-resisting element.
   Diaphragm chord. A diaphragm boundary element perpendicular to the applied load that is assumed to take axial stresses due to the diaphragm moment.
   Diaphragm, unblocked. A diaphragm that has edge nailing at supporting members only. Blocking between supporting structural members at panel edges is not included. Diaphragm panels are field nailed to supporting members.
DIMENSIONS.
   Nominal. The specified dimension plus an allowance for the joints with which the units are to be laid. Nominal dimensions are usually stated in whole numbers. Thickness is given first, followed by height and then length.
   Specified. Dimensions specified for the manufacture or construction of a unit, joint or element.
DIRECT AND CONTINUING SUPERVISION. See Section 28-401.3 of the Administrative Code.
DIRECT EMPLOY. See Section 28-401.3 of the Administrative Code.
DISMANTLING. The final process of taking apart, piece by piece, in a specific sequence, the components of a tower crane. Dismantling shall include jumping.
DISPENSING. The pouring or transferring by other means of any material from a container, tank or similar vessel, which would release dusts, fumes, mists, vapors, or gases to the atmosphere, unless such release is prevented by a device, equipment or system designed for that purpose.
DISPLAY SIGN. The area made available by the sign structure for the purpose of displaying the advertising message.
DOOR, BALANCED. A door equipped with double-pivoted hardware so designed as to cause a semicounterbalanced swing action when opening.
DRAFT STOP. A material, device or construction installed to resist the movement of air within open spaces of concealed areas of building components such as crawl spaces, floor/ceiling assemblies, roof/ceiling assemblies and attics.
DRAG STRUT. See "Collector."
DRILLED DISPLACEMENT PILES. Rotary displacement piles installed by rotating a helical auger segment into the ground with both a vertical force and a torque. The soil is displaced laterally within the ground (with minimum spoil generated) and the void created is filled with grout or concrete.
DRIVEN UNCASED PILES. Driven uncased piles are constructed by driving a steel shell into the soil to shore an unexcavated hole that is later filled with concrete. The steel casing is lifted out of the hole during the deposition of the concrete. Driven uncased piles are not permitted under the provisions of this code.
DRUM. The cylindrical member around which a rope is wound for raising and lowering the load or boom.
DRY-CHEMICAL EXTINGUISHING AGENT. A powder composed of small particles, usually of sodium bicarbonate, potassium bicarbonate, urea-potassium-based bicarbonate, potassium chloride or monoammonium phosphate, with added particulate material supplemented by special treatment to provide resistance to packing, resistance to moisture absorption (caking) and the proper flow capabilities.
DRY (SOIL). Soil that does not exhibit visible signs of moisture content.
DWELLING. A building or structure that is occupied in whole or in part as the home, residence or sleeping place of one or more families.
DWELLING, MULTIPLE. A dwelling that is either rented, leased, let or hired out, to be occupied, or is occupied, as the residence or home of three or more families living independently of each other. A multiple dwelling does not include a building used for occupancies in Groups I-2, I-3 or I-4.
DWELLING, ONE-FAMILY. Any building or structure designed and occupied exclusively for residence purposes on a long-term basis for more than a month at a time by not more than one family. One-family dwelling shall also be deemed to include a dwelling located in a series of one-family dwellings each of which faces or is accessible to a legal street or public thoroughfare, provided that each such dwelling unit is equipped as a separate dwelling unit with all essential services, and also provided that each such unit is arranged so that it may be approved as a legal one-family dwelling.
DWELLING, TWO-FAMILY. Any building or structure designed and occupied exclusively for residence purposes on a long-term basis for more than a month at a time by not more than two families. Two-family dwellings shall also be deemed to include a dwelling located in a series of two-family dwellings each of which faces or is accessible to a legal street or public thoroughfare, provided that each such dwelling is equipped as a separate dwelling with all essential services, and also provided that each such dwelling is arranged so that it may be approved as a legal two-family dwelling.
DWELLING UNIT. A single unit consisting of one or more habitable rooms and occupied or arranged to be occupied as a unit separate from all other units within a dwelling.
DWELLING UNIT (ACCESSIBILITY). As used in Chapter 11 and Appendix E, a single unit providing complete, independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation.
DWELLING UNIT OR SLEEPING UNIT, MULTISTORY. See "Multistory unit".
DWELLING UNIT OR SLEEPING UNIT, TYPE B. See "Type B unit".
EAVE HEIGHT, h. The distance from the ground surface adjacent to the building to the roof eave line at the particular wall. If the distance of the eave varies along the wall, the average distance shall be used.
EFFECTIVE WIND AREA. See ASCE 7.
EGRESS, COURT. A court or yard that provides access to a public right of way for one or more exits.
ELECTRIC SIGN. A sign containing electrical wiring, but not including signs illuminated by an exterior light source.
ELECTRICAL CIRCUIT PROTECTIVE SYSTEM. A specific listed construction of devices, materials, or coatings installed as a fire-resistive barrier system applied to electrical system components, such as cable trays, conduits and other raceways, open run cables and conductors, cables, and conductors in accordance with UL 2196.
ELEMENT (STRUCTURAL). A structural member or structural assembly.
ELEVATOR LANDING. That portion of a floor, balcony, or platform used to receive and discharge passengers or freight adjacent to an elevator hoistway.
EMERGENCY ALARM SYSTEM. A system to provide indication and warning of an emergency condition involving a release of hazardous material or other hazardous material incident.
EMERGENCY CONTROL STATION. An approved location on the premises of a semiconductor fabrication facility staffed by trained personnel that monitor the operation of equipment and systems including alert and alarm signals.
EMERGENCY ESCAPE AND RESCUE OPENING. An operable window, door or other similar device that provides for a means of escape and access for rescue in the event of an emergency.
EMERGENCY VOICE/ALARM COMMUNICATIONS. Dedicated manual or automatic facilities for originating and distributing voice instructions, as well as alert and evacuation signals pertaining to a fire or other emergency, to the occupants of a building.
EMPLOYEE WORK AREA. All or any portion of a space used only by employees and only for work. Corridors, toilet rooms, kitchenettes and break rooms are not employee work areas.
ENGINEERED WOOD RIM BOARD. A full-depth structural composite lumber, wood structural panel, structural glued laminated timber or prefabricated wood I-joist member designed to transfer horizontal (shear) and vertical (compression) loads, provide attachment for diaphragm sheathing, siding and exterior deck ledgers, and provide lateral support at the ends of floor or roof joists or rafters.
ENLARGED BASE PILES. Enlarged base piles are cast-in-place concrete piles constructed with a base that is larger than the diameter of the remainder of the pile. The enlarged base is designed to increase the load-bearing area of the pile in end bearing. Enlarged base piles include piles installed by driving a precast concrete tip or by compacting concrete into the base of the pile to form an enlarged base.
EQUIPMENT. Tools, machinery, or other implements used to facilitate construction or demolition work.
EQUIPMENT PLATFORM. An unoccupied, elevated platform used exclusively for mechanical systems or industrial process equipment, including the associated elevated walkways, stairways, alternating tread devices and ladders necessary to access the platform (see Section 505.3).
ERECTION. The assembly and placement of tower crane sections and components into place, including all operations incidental thereto. Erection shall include jumping.
ESSENTIAL FACILITIES. Buildings and other structures that are intended to remain operational in the event of extreme environmental loading from flood, wind, snow or earthquakes.
EXCAVATION. The removal of earth from its natural position; except for any incidental removal that occurs during the course of auguring, drilling, vibrating, or driving.
EXHAUSTED ENCLOSURE. A device, typically consisting of a hood equipped with a fan, that serves to capture and exhaust fumes, mist, vapors and gases generated at a workstation or other local environment. An exhausted enclosure does not include a room provided with general ventilation.
EXISTING CONSTRUCTION (FOR FLOOD ZONE PURPOSES). See Section G201.1.2.
EXISTING STRUCTURE (FOR FLOOD ZONE PURPOSES). See Section G201.1.2.
EXIT. That portion of a means of egress system, which is separated from other interior spaces of a building or structure by fire-resistance-rated construction and opening protective as required to provide a protected path of egress travel between the exit access and the exit discharge. Exits include exterior exit doors at the level of exit discharge, interior exit stairways and ramps, exit passageways, exterior exit stairways, exterior exit ramps and horizontal exits, but do not include access stairs, aisles, exit access doors opening to corridors, or corridors.
EXIT ACCESS. That portion of a means of egress system that leads from any occupied portion of a building or structure to an exit.
EXIT ACCESS DOORWAY. A door or access point along the path of egress travel from an occupied room, area or space where the path of egress enters an intervening room, corridor, unenclosed exit access stair or unenclosed exit access ramp.
EXIT ACCESS RAMP. A ramp within the exit access portion of the means of egress system.
EXIT ACCESS STAIRWAY. A stairway within the exit access portion of the means of egress system.
EXIT DISCHARGE. That portion of a means of egress system between the termination of an exit and a public way.
EXIT DISCHARGE, LEVEL OF. The story at the point at which an exit terminates and an exit discharge begins.
EXIT, HORIZONTAL. An exit that provides a path of egress travel from one building to an area in another building on approximately the same level, or a path of egress travel through or around a wall or partition to an area on approximately the same level in the same building, or a bridge or tunnel between two buildings, which affords safety from fire and smoke from the area of incidence and areas communicating therewith.
EXIT PASSAGEWAY. An exit component that is separated from other interior spaces of a building or structure by fire-resistance-rated construction and opening protectives, and provides for a protected path of egress travel in a horizontal direction to an exit component or to the exit discharge.
EXPANDED VINYL WALL COVERING. Wall covering consisting of a woven textile backing, an expanded vinyl base coat layer and a non-expanded vinyl skin coat. The expanded base coat layer is a homogenous vinyl layer that contains a blowing agent. During processing, the blowing agent decomposes, causing this layer to expand by forming closed cells. The total thickness of the wall covering is approximately 0.055 inch to 0.070 inch (1.4 mm to 1.8 mm).
EXPLOSION. An effect produced by the sudden violent expansion of gases, whether or not accompanied by a shock wave or disruption, of enclosing materials, including the effects of the following sources of explosion:
   1.   Chemical changes such as rapid oxidation, deflagration or detonation, decomposition of molecules and runaway polymerization (usually detonations).
   2.   Physical changes such as pressure tank ruptures.
   3.   Atomic changes (nuclear fission or fusion).
EXPLOSIVE. A chemical compound, mixture or device, the primary or common purpose of which is to function by explosion. The term includes, but is not limited to, dynamite, black powder, pellet powder, initiating explosives, detonators, safety fuses, squibs, detonating cord, igniter cord and igniters.
The term "explosive" includes any material determined to be within the scope of Chapter 40 of Title 18 of the United States Codes, and any material classified as an explosive by the hazardous materials regulations of the United States Department of Transportation, as set forth in 49 CFR Section 173.52, except fireworks. Explosives are classified in accordance with the following United States Department of Transportation classification and other terms in common usage:
   UN/DOTn Class 1 explosives.
      Division 1.1. Explosives that present a mass explosion hazard.
      Division 1.2. Explosives that present a projection hazard but not a mass explosion hazard.
      Division 1.3. Explosives that present a fire hazard and either a minor blast hazard or a minor projection hazard, or both, but not a mass explosion hazard.
      Division 1.4. Explosives that present a minor explosion hazard. The explosive effects are largely confined to the package and no projection of fragments of appreciable size or range is to be expected. Such explosives are not subject to mass explosion when exposed to fire.
      Division 1.5. Explosives that present a mass explosion hazard but which are so insensitive that there is very little probability of initiation or of transition from burning to detonation under normal conditions of transport.
      Division 1.6. Explosives consisting of extremely insensitive articles that do not present a mass explosion hazard, and present a negligible probability of accidental initiation or propagation.
   High explosive. Explosives, including dynamite, that, when detonated, are characterized by a high rate of reaction, high pressure development, and the presence of a detonation wave, and that can be caused to detonate by means of a No. 8 test blasting cap, when unconfined.
   Low explosive. Explosives that will burn or deflagrate when ignited, and which are characterized by a rate of reaction that is less than the speed of sound, and low pressure development. Examples of low explosives include black powder, igniter cords, igniters, safety fuses, small arms ammunition and primers, and propellants, 1.3C.
   Mass-detonating explosives. Division 1.1, 1.2 and 1.5 explosives that, whether individually or in combination, or loaded into ammunition or containers, explode virtually instantaneously when a small portion is subjected to fire, concussion, impact, the impulse of an initiating agent, or the effect of a considerable discharge of energy from without, with severe explosive effect, including the potential for structural damage to adjacent objects, and explosive propagation to other explosives stored in proximity, such that two or more quantities in proximity must be considered as one for quantity-distance purposes.
EXTERIOR EXIT RAMP. An exit component that serves to meet one or more means of egress design requirements, such as required number of exits or exit access travel distance, and is open to yards, courts or public ways.
EXTERIOR EXIT STAIRWAY. An exit component that serves to meet one or more means of egress design requirements, such as required number of exits or exit access travel distance, and is open to yards, courts or public ways.
EXTERIOR INSULATION AND FINISH SYSTEMS (EIFS). EIFS are nonstructural, nonload-bearing, exterior wall cladding systems that consist of an insulation board attached either adhesively or mechanically, or both, to the substrate, an integrally reinforced base coat and a textured protective finish coat.
EXTERIOR INSULATION AND FINISH SYSTEMS (EIFS) WITH DRAINAGE. An EIFS that incorporates a means of drainage applied over a water-resistive barrier.
EXTERIOR SURFACES. Weather-exposed surfaces.
EXTERIOR WALL. A wall, bearing or nonbearing, that is used as an enclosing wall for a building, other than a fire wall, and that has a slope of 60 degrees (1.05 rad) or greater with the horizontal plane.
EXTERIOR WALL COVERING. A material or assembly of materials applied on the exterior side of exterior walls for the purpose of providing a weather-resisting barrier, insulation or for aesthetics, including but not limited to, veneers, siding, exterior insulation and finish systems, architectural trim and embellishments such as cornices, soffits, facias, gutters and leaders.
EXTERIOR WALL ENVELOPE. A system or assembly of exterior wall components, including exterior wall finish materials, that provides protection of the building structural members, including framing and sheathing materials, and conditioned interior space, from the detrimental effects of the exterior environment.
F RATING. The time period that the through-penetration firestop system limits the spread of fire through the penetration when tested in accordance with ASTM E 814 or UL 1479.
FABRIC PARTITION. A partition consisting of a finished surface made of fabric, without a continuous rigid backing, that is directly attached to a framing system in which the vertical framing members are spaced greater than 4 feet (1219 mm) on center.
FABRICATION AREA. An area within a semiconductor fabrication facility in which processes using hazardous production materials are conducted.
FACILITY. All or any portion of buildings, structure, site improvements, elements and pedestrian or vehicular routes located on a site.
FACTORED LOAD. The product of a nominal load and a load factor.
FAMILY.
   1.   A single person occupying a dwelling unit and maintaining a common household with not more than two boarders, roomers or lodgers;
   2.   Two or more persons related by blood, adoption, legal guardianship, marriage or domestic partnership; occupying a dwelling unit and maintaining a common household with not more than two boarders, roomers or lodgers;
   3.   Not more than three unrelated persons occupying a dwelling unit and maintaining a common household;
   4.   Not more than three unrelated persons occupying a dwelling unit in a congregate housing or shared living arrangement and maintaining a common household;
   5.   Members of a group home;
   6.   Foster children placed in accordance with provisions of the New York State Social Services Law, their foster parent(s), and other persons related to the foster parents by blood, marriage or domestic partnership; where all residents occupy and maintain a common household with not more than two boarders, roomers or lodgers; or
   7.   Up to seven unrelated students enrolled at a single accredited college or university occupying a student apartment and maintaining a common household pursuant to a lease, sublease, or occupancy agreement directly with such college or university, provided that:
      7.1.   The entire structure in which the dwelling unit is located is fully sprinklered in accordance with Chapter 9 of this code;
      7.2.   Such occupancy does not exceed the maximums contained in Section 27-2075(a) of the New York City Housing Maintenance Code;
      7.3.   Prior to commencement of such occupancy, and on an annual basis thereafter such college or university has submitted a fire safety plan containing fire safety and evacuation procedures for such dwelling unit that is acceptable to the Fire Commissioner and in compliance with any rules promulgated by the Fire Commissioner; and
      7.4.   The dwelling unit complies with additional occupancy and construction requirements as may be established by rule by the Housing Preservation and Development Commissioner.
   A common household is deemed to exist if all household members have access to all parts of the dwelling unit. Lack of access to all parts of the dwelling unit establishes a rebuttable presumption that no common household exists.
FENESTRATION. Skylights, roof windows, vertical windows (fixed or moveable), opaque doors, glazed doors, glazed block and combination opaque/glazed doors. Fenestration includes products with glass and nonglass glazing materials.
FIBERBOARD. A fibrous, homogeneous panel made from lignocellulosic fibers (usually wood or cane) and having a density of less than 31 pounds per cubic foot (pcf) (497 kg/m 3 ) but more than 10 pcf (160 kg/m 3 ).
FIBER REINFORCED POLYMER. A polymeric composite material consisting of reinforcement fibers, such as glass, impregnated with a fiber-bonding polymer which is then molded and hardened. Fiber-reinforced polymers are permitted to contain cores laminated between fiber-reinforced polymer facings.
FIBER-CEMENT SIDING. A manufactured, fiber-reinforcing product made with an inorganic hydraulic or calcium silicate binder formed by chemical reaction and reinforced with discrete organic or inorganic nonasbestos fibers, or both. Additives that enhance manufacturing or product performance are permitted. Fiber cement siding products have either smooth or textured faces and are intended for exterior wall and related applications.
FIBERGLASS REINFORCED POLYMER. A polymeric composite material consisting of glass reinforcement fibers impregnated with a fiber-binding polymer which is then molded and hardened.
FILM   SIGN . A flat section of a material that is extremely thin in comparison to its length and breadth and has a nominal maximum thickness of 0.01 inch (0.25 mm).
FIRE   ALARM   BOX , MANUAL . See "Manual Fire Alarm Box."
FIRE   ALARM   CONTROL   UNIT . A system component that receives inputs from automatic and manual fire alarm devices and may be capable of supplying power to detection devices and transponders or off-premises transmitters. The control unit may be capable of providing a transfer of power to the notification appliances and transfer of condition to relays or devices.
FIRE   ALARM   SIGNAL . A signal initiated by a fire alarm-initiating device such as a manual fire alarm box, automatic fire detector, waterflow switch, or other device whose activation is indicative of the presence of a fire or fire signature.
FIRE   ALARM   SYSTEM . A system or portion of a combination system consisting of components and circuits arranged to monitor and annunciate the status of fire alarm or supervisory signal-initiating devices and to initiate the appropriate response to those signals.
FIRE   AREA . The aggregate floor area enclosed and bounded by fire walls, fire barriers, exterior walls and/or horizontal assemblies of a building. Areas of the building not provided with surrounding walls shall be included in the fire area if such areas are included within the horizontal projection of the roof or floor next above.
FIRE   BARRIER . A fire-resistance-rated wall assembly of materials complying with Section 707 designed to restrict the spread of fire in which continuity of the fire-resistance rating is maintained.
FIRE   COMMAND   CENTER . The principal attended or unattended location where the status of detection, alarm communications and control systems is displayed, and from which the systems can be manually controlled.
FIRE   DAMPER . See "Dampers, Types of."
FIRE   DETECTOR , AUTOMATIC . A device designed to detect the presence of a fire signature and to initiate action.
FIRE   DOOR . The door component of a fire door assembly.
FIRE   DOOR   ASSEMBLY . Any combination of a fire door, frame, hardware, and other accessories that together, as an opening protective, provide a specific degree of fire protection to the opening.
FIRE   DOOR   ASSEMBLY , FLOOR . See "Floor fire door assembly."
FIRE   EXIT   HARDWARE . Panic hardware that is listed for use on fire door assemblies.
FIRE   LANE. A public or private road, roadway lane, parking lot lane or other surface designed to allow vehicular access, that has been specifically designated by means of signs or roadway markings as a priority thoroughfare for fire apparatus.
FIRE PARTITION. A vertical assembly of materials complying with Section 708, designed to restrict the spread of fire in which openings are protected.
FIRE PROTECTION RATING. The period of time that an opening protective assembly will maintain the ability to confine a fire as determined by tests prescribed in Section 716. Ratings are stated in hours or minutes.
FIRE PROTECTION SYSTEM. Approved devices, equipment and systems or combinations of systems used to detect a fire, activate an alarm, extinguish or control a fire, control or manage smoke and products of a fire or any combination thereof.
FIRE PUMP. A pump exclusively used to boost water supply pressures in a fire protection system.
FIRE PUMP, AUTOMATIC STANDPIPE. A fire pump located at or below street level or as required, at the design flood elevation, that supplies the lower 300 feet (91.4 m) of an automatic standpipe system or a combined standpipe and sprinkler system. This does not apply to manual wet standpipe systems which are combined with sprinkler systems.
FIRE PUMP, FOAM. A fire pump used to boost water supply pressures in a fire protection system where such system uses firefighting foam as an additive.
FIRE PUMP, LIMITED SERVICE. A fire pump with a motor rating not exceeding 30 hp and utilizing a limited service fire pump controller.
FIRE PUMP, SPECIAL SERVICE. A fire pump that is located above street level, and above flood level, and that receives its water supply from a gravity tank or suction tank.
FIRE PUMP, SPRINKLER BOOSTER PUMP. A fire pump that supplies sprinkler systems only.
FIRE PUMP, WATER MIST SYSTEM. A fire pump used to boost water supply pressures in a fire protection system where such system utilizes water misting technology.
FIRE RESISTANCE. That property of materials or their assemblies that prevents or retards the passage of excessive heat, hot gases or flames under conditions of use.
FIRE SAFETY FUNCTIONS. Building and fire control functions that are intended to increase the level of life safety for occupants or to control the spread of harmful effects of fire.
FIRE SEPARATION DISTANCE. The distance measured from the building face to one of the following:
   1.   The closest interior tax lot line;
   2.   To the centerline of a street, an alley or public space; or
   3.   To an imaginary line between two buildings on the same tax lot.
   The distance shall be measured at right angles from the face of the wall.
FIRE WALL. A fire-resistance-rated smoke-tight wall having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall.
FIRE WINDOW ASSEMBLY. A window, as an opening protective, constructed and glazed to give protection against the passage of fire, smoke and hot gases.
FIREBLOCKING. A building material or materials approved for use as fireblocking to resist the free passage of flame or hot gases to other areas of the building through concealed spaces.
FIRECUT. A sloping cut on the ends of wood beams, joists and rafters resting on masonry or concrete walls.
FIREPLACE. A hearth and fire chamber or similar prepared place in which a fire may be made and that is built in conjunction with a chimney.
FIREPLACE THROAT. The opening between the top of the firebox and the smoke chamber.
FIRE-RATED GLAZING. Glazing with either a fire protection rating or a fire-resistance rating.
FIRE-RESISTANCE RATING. The period of time a building element, component or assembly maintains the ability to withstand fire exposure, continues to perform a given structural function, or both, as determined by the tests, or the methods based on tests, prescribed in Section 703.
FIRE-RESISTANT JOINT SYSTEM. An assemblage of specific materials or products that are designed, tested, and fire-resistance rated in accordance with either ASTM E 1966 or UL 2079 to resist for a prescribed period of time the passage of fire through joints made in or between fire-resistance-rated assemblies.
FIRESTOPPING. A through-penetration firestop or a membrane penetration firestop.
FIREWORKS. Any article or device that does not present a mass explosion hazard, that is manufactured or used to produce a visible or audible effect for entertainment or other display purposes by combustion, deflagration or detonation that meets the definition of 1.4G fireworks or 1.3G fireworks as set forth herein.
   Fireworks, 1.3G. Large firework devices, classified as UN0335 by the United States Department of Transportation regulations, intended for use in fireworks displays and designed to produce audible or visible effects by combustion, deflagration or detonation including firecrackers containing more than 130 milligrams (2 grains) of explosive composition, aerial shells containing more than 40 grams of pyrotechnic material, and other display pieces which exceeds the limits for classification as 1.4G fireworks.
   Fireworks, 1.4G. Small firework devices, classified as UN 0336 by United States Department of Transportation regulations, containing restricted amounts of pyrotechnic materials designed primarily to produce visible or audible effects by combustion.
FISSURED (SOIL). A soil material that has a tendency to break along definite planes of fracture with little resistance, or a material that exhibits open cracks, such as tension cracks, in an exposed surface.
FIXED BASE OPERATOR (FBO). A commercial business granted the right by the airport sponsor to operate on an airport and provide aeronautical services, such as fueling, hangaring, tie-down and parking, aircraft rental, aircraft maintenance and flight instruction.
FIXED HEADED PILE (DEEP FOUNDATION). A pile connected to a pile cap in a manner that prevents rotation of the pile head.
FIXED SEATING. Furniture or fixture designed and installed for the use of sitting and secured in place including bench-type seats and seats with or without backs or arm rests.
FLAME SPREAD. The propagation of flame over a surface.
FLAME SPREAD INDEX. A comparative measure, expressed as a dimensionless number, derived from visual measurements of the spread of flame versus time for a material tested in accordance with ASTM E 84 or UL 723.
FLAMMABLE GAS. A material which has a boiling point and becomes a gas at 68°F (20°C) or less at 14.7 pounds per square inch absolute (psia) (101 kPa) of pressure which:
   1.   Is ignitable at 14.7 psia (101 kPa) when in a mixture of 13 percent or less by volume with air, in accordance with testing procedures set forth in ASTM E 681; or
   2.   Has a flammable range at 14.7 psia (101 kPa) with air of at least 12 percent, regardless of the lower explosive limit, in accordance with testing procedures set forth in ASTM E 681.
   The limits specified shall be determined at 14.7 psia (101 kPa) of pressure and a temperature of 68°F (20°C) in accordance with ASTM E 681.
FLAMMABLE LIQUEFIED GAS. A liquefied gas that, under a charged pressure, is partially liquid at a temperature of 68°F (20°C) and which is flammable.
FLAMMABLE LIQUID. For the purposes of transportation, a flammable liquid as defined in the regulations of the United States Department of Transportation, as set forth in 49 CFR 173.120. For all other purposes, a liquid, other than a compressed gas or cryogenic fluid, having a closed cup flash point below 100°F (38°C) classified as follows:
   Class IA. Liquids having a flash point below 73°F (23°C) and a boiling point below 100°F (38°C).
   Class IB. Liquids having a flash point below 73°F (23°C) and a boiling point at or above 100°F (38°C).
   Class IC. Liquids having a flash point at or above 73°F (23°C) and below 100°F (38°C).
FLAMMABLE MATERIAL. A material capable of being readily ignited from common sources of heat or at a temperature of 600°F (316°C) or less.
FLAMMABLE SOLID. A solid, other than a blasting agent or other explosive, whether in elemental or alloy form, that is capable of causing fire through friction, absorption or moisture, spontaneous chemical change, or heat retained from manufacturing or processing, or which has an ignition temperature below 212°F (100°C) or which burns so vigorously and persistently when ignited as to create a serious hazard. A chemical shall be considered a flammable solid if upon testing using the method prescribed in CPSC regulations, as set forth in 16 CFR 1500.44, if it ignites and burns with a self-sustained flame at a rate greater than 0.1 inch (2.5 mm) per second along its major axis.
FLAMMABLE VAPORS OR FUMES. The concentration of flammable constituents in air that exceed 25 percent of their lower flammable limit (LFL).
FLASH POINT. The minimum temperature in degrees Fahrenheit at which a liquid will give off sufficient vapors to form an ignitable mixture with air near the surface or in the container, but will not sustain combustion. The flash point of a liquid shall be determined by appropriate test procedure and apparatus as specified in ASTM D 56, ASTM D 93 or ASTM D 3278.
FLIGHT. A continuous run of rectangular treads, winders or combination thereof from one landing to another.
FLOOD or FLOODING. A general and temporary condition of partial or complete inundation of normally dry land from:
   1.    The overflow of inland or tidal waters.
   2.    The unusual and rapid accumulation or runoff of surface waters from any source.
FLOOD DESIGN CLASS. See Section G201.1.2.
FLOOD HAZARD AREA. The following two areas:
   1.   The area within a flood plain subject to a 1-percent or greater chance of flooding in any year. Also defined as the "special flood hazard area".
   2.   Where buildings are classified as Flood Design Class 4, the area within a flood plain delineated as shaded X-Zones.
FLOOD INSURANCE RATE MAP (FIRM). An official map of a community on which the Federal Emergency Management Agency (FEMA) has delineated both the special flood hazard areas and the risk premium zones applicable to the community.
FLOOD INSURANCE STUDY (FIS). The official report provided by the Federal Emergency Management Agency (FEMA) containing the Flood Insurance Rate Map (FIRM), the water surface elevation of the base flood and supporting technical data.
FLOOD-DAMAGE-RESISTANT MATERIALS. Any construction material, including finishes, capable of withstanding direct and prolonged contact with floodwaters without sustaining any damage that requires more than cosmetic repair.
FLOODPROOFING, DRY. For buildings and structures that are nonresidential (for flood zone purposes), a combination of design modifications that results in the building's or structure's being water tight to the design flood elevation, including the attendant utility and sanitary facilities, with walls substantially impermeable to the passage of water and with structural components having the capacity to resist loads as identified in ASCE 7.
FLOODPROOFING, WET. A floodproofing method designed to permit parts of the structure below the design flood elevation that are used for parking, storage, building access, or crawl space to intentionally flood, by equalizing hydrostatic pressures and by relying on the use of flood damage-resistant materials and construction techniques.
FLOODWAY. The channel of the river, creek or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height. Floodways are mapped only in the Boroughs of the Bronx and Staten Island.
FLOOR AREA, GROSS. The floor area within the inside perimeter of the exterior walls of the building under consideration, exclusive of courts, without deduction for corridors, stairways, closets, the thickness of interior walls, columns or other features. The floor area of a building, or portion thereof, not provided with surrounded exterior walls shall be the usable area under the horizontal projection of the roof or floor above. The gross floor area shall not include interior courts.
FLOOR AREA, NET. The actual occupied area not including the thickness of walls, partitions, columns, furred-in spaces, fixed cabinets, equipment, and unoccupied accessory areas such as corridors, stairways, toilet rooms, mechanical rooms and closets.
FLOOR FIRE DOOR ASSEMBLY. A combination of a fire door, a frame, hardware and other accessories installed, as an opening protective, in a horizontal plane, which together provide a specific degree of fire protection to a through opening in a fire-resistance-rated floor (see Section 712.1.13.1).
FLOOR SURFACE AREA. See Section 28-101.4.5.2 of the Administrative Code.
FLUE. A passageway within a chimney or vent through which gaseous combustion products pass.
FLUE APPLIANCE. The passage(s) within an appliance through which combustion products pass from the combustion chamber of the appliance to the draft hood inlet opening on an appliance equipped with a draft hood or to the outlet of the appliance on an appliance not equipped with a draft hood.
FLUE GASES. Products of combustion and excess air.
FLUE LINER (LINING). A system or material used to form the inside surface of a flue in a chimney vent, for the purpose of protecting the surrounding structure from the effects of combustion products and for conveying combustion products without leakage into the atmosphere.
FLY GALLERY. A raised floor area above a stage from which the movement of scenery and operation of other stage effects are controlled.
FLY-THROUGH CONDITIONS. One or more panels of glass that provide a clear line of sight through such elements creating the illusion of a void leading to the other side, including parallel glass elements, at a distance of 17 feet (5182 mm) or less, or a convergence of glass sides creating a perpendicular, acute or obtuse corner.
FOAM PLASTIC INSULATION. A plastic that is intentionally expanded by the use of a foaming agent to produce a reduced-density plastic containing voids consisting of open or closed cells distributed throughout the plastic for thermal insulating or acoustical purposes and that has a density less than 20 pounds per cubic foot (pcf) (320 kg/m 3 ).
FOAM-EXTINGUISHING SYSTEM. A special system discharging a foam made from concentrates mechanically over the area to be protected.
FOLDING AND TELESCOPIC SEATING. Tiered seating having an overall shape and size that is capable of being reduced for purposes of moving or storing and is not a building element.
FOOD COURT. See Section 402.2.
FOOTING. A foundation element consisting of an enlargement of a foundation pier or foundation wall, wherein the soil materials along the side of and underlying the element may be visually inspected prior to and during its construction.
FOUNDATION PIER. An isolated vertical foundation member whose horizontal dimension measured at right angles to its thickness does not exceed three times its thickness and whose height is equal to or less than four times its thickness.
FREE HEADED PILE. A pile with a head that is free to rotate.
FRONTAGE SPACE. A street or an open space adjoining a building not less than 30 feet (9144 mm) in any dimension. Such open space shall be accessible from a street by a driveway, lane, private road or alley at least 20 feet (6096 mm) in width. Such open space including accessways shall be permanently maintained free of all obstructions that might interfere with its use by the Fire Department.
FUNCTIONALLY DEPENDENT FACILITY. See Section G201.1.2.
GABLE. The triangular portion of a wall beneath the end of a dual-slope, pitched, or mono-slope roof or portion thereof and above the top plates of the story or level of the ceiling below.
GAS CABINET. A fully enclosed, noncombustible enclosure used to provide an isolated environment for compressed gas containers in storage or use, including any doors and access ports for exchanging containers and accessing pressure-regulating controls.
GAS ROOM. A separately ventilated, fully enclosed room in which only compressed gases and associated equipment and supplies are stored or used.
GEOTECHNICAL CAPACITY OF DEEP FOUNDATIONS. The load that can be supported by the soil or rock surrounding deep foundation as determined using a recognized method of analysis or as established by load tests. The geotechnical capacity can be developed through skin friction, end bearing, or a combination thereof.
GLASS FIBERBOARD. Fibrous glass roof insulation consisting of inorganic glass fibers formed into rigid boards using a binder. The board has a top surface faced with asphalt and kraft reinforced with glass fiber.
GRADE (LUMBER). The classification of lumber in regard to strength and utility in accordance with American Softwood Lumber Standard DOC PS 20 and the grading rules of an approved lumber rules-writing agency.
GRADE PLANE. A reference plane representing the level of the curb as established by the city engineer in the Borough President's office, measured at the center of the front of a building. Where a building faces on more than one street, the grade plane shall be the average of the levels of the curbs at the center of each front.
   Exception: The grade plan shall not be referenced to the level of the curb, but shall be considered the average elevation of the final grade adjoining all exterior walls of a building, calculated from final grade elevations taken at intervals of 10 feet (3048 mm) around the perimeter of the building where:
      1.   No curb elevation has been legally established on the city map; or
      2.   Every part of the building is setback more than 25 feet (7620 mm) from a street line.
GRANDSTAND. Tiered seating supported on a dedicated structural system and two or more rows high and is not a building element (see "Bleachers").
GRANULAR SOIL. Gravel, sand, or silt (coarse grained soil) with little or no clay content. Granular soil has no cohesive strength. Some moist granular soils exhibit apparent cohesion. Granular soil cannot be molded when moist and crumbles easily when dry.
GREEN ROOF SYSTEM. See definition for "Vegetative Roof."
GRIDIRON. The structural framing over a stage supporting equipment for hanging or flying scenery and other stage effects.
GROSS LEASABLE AREA. See Section 402.2.
GROUND SIGN. A billboard or similar type of sign that is supported by one or more uprights, poles or braces in or upon the ground other than a combination sign or pole sign, as defined by this code.
GROUP HOME. A facility for the care and maintenance of not fewer than seven nor more than 12 children, supervised by the New York State Board of Social Welfare, and operated pursuant to and meeting any additional construction requirements of Section 374-C of the New York State Social Services Law and applicable regulations of the New York State Department of Social Services. Such a facility occupied by more than 12 children shall be classified as Group I-1.
GROUT. A plastic mixture of cementitious materials, aggregates, and water, with or without admixtures, initially produced to pouring consistency without segregation of the constituents during placement, or the equivalent of such mixtures, conforming to ASTM C 476.
GUARD. A building component or a system of building components located at or near the open sides of elevated walking surfaces that minimizes the possibility of a fall from the walking surface to a lower level.
GUARDRAIL SYSTEM (SCAFFOLD). A vertical barrier as described in Section 3314.8 consisting of, but not limited to, toprails, midrails and posts, erected to prevent falling from a scaffold platform or walkway to lower levels.
GUY. A rope used to steady or secure the mast or other members in the desired position.
GYPSUM BOARD. Gypsum wallboard, gypsum sheathing, gypsum base for gypsum veneer plaster, exterior gypsum soffit board, predecorated gypsum board or water-resistant gypsum backing board complying with the standards listed in Tables 2506.2, 2507.2 and Chapter 35.
GYPSUM PANEL PRODUCTS. The general name for a family of sheet products consisting essentially of gypsum.
GYPSUM PLASTER. A mixture of calcined gypsum or calcined gypsum and lime and aggregate and other approved materials as specific in this code.
GYPSUM VENEER PLASTER. Gypsum plaster applied to an approved base in one or more coats normally not exceeding 1/4 inch (6.4 mm) in total thickness.
HABITABLE SPACE. All rooms and spaces within a dwelling unit in Group R or I-1, including bedrooms, living rooms, studies, recreation rooms, kitchens, dining rooms and other similar spaces.
   Exception: The following spaces within a dwelling unit shall not be considered habitable space:
      1.   A dining space 55 square feet (5.1 m 2 ) or less located off a living room, foyer or kitchen;
      2.   A kitchenette;
      3.   A bathroom or toilet room;
      4.   A laundry room; and
      5.   A corridor, passageway, or private hall; and a foyer used as an entrance hall in a dwelling unit: not exceeding 10 percent of the total floor area of the dwelling unit; or not exceeding 20 percent of the floor area of the dwelling unit where every habitable room is at least 20 percent larger than the required minimum room sizes established by the New York City Housing Maintenance Code.
HALL CALL CONSOLE. A collection of features arranged in close proximity to one another, the purpose of which is to call a destination-oriented elevator car to an elevator landing on which the console is provided. Such features can be provided as a single assembly or as individual elements functioning together.
HALOGENATED EXTINGUISHING SYSTEM. A fire-extinguishing system using one or more atoms of an element from the halogen chemical series; fluorine, chlorine, bromine and iodine.
HANDHELD DEVICE (DEMOLITION). Equipment, mechanical or non-mechanical, utilized to physically demolish a building or structure, or elements of a building or structure, that is held, lifted, moved, and operated by a single person. A handheld device shall also include any item accessory to such equipment, including but not limited to a compressor, regardless of if such accessory item is held, lifted, moved, and operated by a single person. A handheld device does not include remote controlled equipment.
HANDLING (HAZARDOUS MATERIAL). The movement of a material in its container, the removal of the material from its container, or any other action or process that may affect the material, other than its storage or use.
HANDRAIL. A horizontal or sloping rail intended for grasping by the hand for guidance or support.
HARDBOARD. A fibrous-felted, homogeneous panel made from lignocellulosic fibers consolidated under heat and pressure in a hot press to a density not less than 31 pcf (497 kg/m 3 ).
HAZARDOUS MATERIALS. Those chemicals or substances that are physical hazards or health hazards as defined and classified in the New York City Fire Code and this code, whether the materials are in usable or waste condition.
HAZARDOUS PRODUCTION MATERIAL (HPM). A solid, liquid or gas associated with semiconductor manufacturing that has a degree-of-hazard rating in health, flammability or instability of Class 3 or 4 as defined in NFPA 704 and that is used directly in research, laboratory or production processes that have as their end product materials that are not hazardous.
HEAD JOINT. Vertical mortar joint placed between masonry units within the wythe at the time the masonry units are laid.
HEALTH HAZARD. A classification of a chemical for which there is statistically significant evidence that acute or chronic health effects are capable of occurring in exposed persons. The term "health hazard" includes chemicals that are toxic or highly toxic, and corrosive.
HEAVY DUTY SCAFFOLD. A supported scaffold capable of supporting loads of up to 75 pounds per square foot (366.15 kg/m 2 ), and not more than those imposed by workers and heavy material, including but not limited to stone.
HEAVY DUTY SIDEWALK SHED. A sidewalk shed designed to carry a live load of at least 300 pounds per square foot (1465 kg/m 2 ).
HEIGHT, BUILDING. The vertical distance from the grade plane to the average height of the highest roof surfaces.
HELICAL PILES. Helical piles are manufactured deep foundation steel elements consisting of a shaft and one or more helical bearing plates (helices) screwed into the ground by application of torque on the shaft. The various products marketed as screw piles, torque anchors, and helical piles are considered helical piles.
HELIPAD. A structural surface that is used for the landing, taking off, taxiing and parking of helicopters.
HELIPORT. An area of land or water or a structural surface that is used, or intended for the use, for the landing and taking off of helicopters, and any appurtenant areas that are used, or intended for use, for heliport buildings or other heliport facilities.
HELISTOP. The same as "heliport," except that no fueling, defueling, maintenance, repairs or storage of helicopters is permitted.
HIGHLY TOXIC MATERIAL. A chemical that is lethal at the following doses or concentrations:
   1.   A chemical that has a median lethal dose (LD 50 ) of 50 milligrams or less per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each;
   2.   A chemical that has a median lethal dose (LD 50 ) of 200 milligrams or less per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between 2 and 3 kilograms each; or
   3.   A chemical that has a median lethal concentration (LD 50 ) in air of 200 parts per million by volume or less of gas or vapor, or 2 milligrams per liter or less of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 300 grams each.
HIGH-PRESSURE BOILER. See Section 28-401.3 of the Administrative Code.
HIGH-PRESSURE DECORATIVE EXTERIOR-GRADE COMPACT LAMINATE (HPL). An exterior wall covering fabricated using HPL in a specific assembly including joints, seams, attachments, substrate, framing and other details as appropriate to a particular design.
HIGH-RISE BUILDING. A building with an occupied floor located more than 75 feet (22 860 mm) above the lowest level of fire department vehicle access.
HISTORIC STRUCTURE. A building or structure which is a designated New York City landmark or interior landmark, is located within a designated New York City historic district, or is listed on the New York State or National Register of Historic Places.
HISTORIC STRUCTURE (FLOOD-RESISTANT CONSTRUCTION). See Section G201.1.2.
HOISTING EQUIPMENT. Power or manually operated equipment that raises or lowers a suspended load. The definition of hoisting equipment shall also include a hoisting machine, bucket hoist, material hoist, personnel hoist, or industrial rope access equipment. The definition of hoisting equipment shall not include an elevator, mast climber, or scaffold.
HOISTING MACHINE. A power operated machine that lifts or lowers a suspended load utilizing a drum and a rope. The definition of hoisting machine shall also include a crane, derrick, cableway, or telehandler. The definition of hoisting machine shall not include an elevator, mast climber, or scaffold.
HOISTING MECHANISM. A hoist drum and rope reeving system used for lifting and lowering loads.
HOISTWAY. The hoistway is the opening through a building or structure for the travel of elevators, dumbwaiters, or material lifts, extending from the pit floor to the roof or floor above.
HOLD-DOWN. See "TIE-DOWN".
HORIZONTAL ASSEMBLY. A fire-resistance-rated floor or roof assembly of materials designed to restrict the spread of fire in which continuity of the fire-resistance rating is maintained.
HOSPITALS ANDPSYCHIATRIC CENTERS. See Section 308.2.
HOUSING UNIT. See Section 408.1.1.
H-PILES. Steel H-piles are constructed by driving a steel H-shaped section into the ground.
HPM FLAMMABLE LIQUID. An HPM liquid that is defined as either a Class I flammable liquid or a Class II or Class IIIA combustible liquid.
HPM ROOM. A room used in conjunction with or serving a Group H-5 occupancy, where HPM is stored or used and that is classified as a Group H-2, H-3 or H-4 occupancy.
HURRICANE-PRONE REGIONS. New York City is within the hurricane-prone region for Risk Category II, III, and IV buildings.
HYDROGEN FUEL GAS ROOM. A separately ventilated, fully enclosed room designed to exclusively house the generation of gaseous hydrogen for immediate on-premises use in indoor fuel cells or other energy production process, and incidental indoor storage of gaseous hydrogen. A hydrogen fuel gas room is not intended to house the production or dispensing of hydrogen motor fuel.
I-4 MIX. A type of heavy duty asphaltic concrete mix containing 0.75 inch (19 mm) nominal maximum size aggregate with 25 percent to 50 percent of the aggregate capable of passing through a No. 8 sieve and in which all sand contained in the mix is crushed.
ICE-SENSITIVE STRUCTURE. A structure for which the effect of an atmospheric ice load governs the design of a structure or portion thereof. This includes, but is not limited to, lattice structures, guyed masts, overhead lines, light suspension and cable-stayed bridges, aerial cable systems (e.g., for ski lifts or logging operations), amusement rides, open catwalks and platforms, flagpoles and signs.
IMMEDIATELY DANGEROUS TO LIFE AND HEALTH (IDLH). The concentration of air-borne contaminants that poses a threat of death, immediate or delayed permanent adverse health effects, or effects that could prevent escape from such an environment as established by the National Institute of Occupational Safety and Health (NIOSH) based on both toxicity and flammability. It generally is expressed in parts per million by volume (ppm v/v) or milligrams per cubic meter (mg/m 3 ). If adequate data do not exist for precise establishment of IDLH concentrations, an independent certified industrial hygienist, industrial toxicologist, appropriate regulatory agency or other source approved by the Fire Commissioner shall make such determination.
IMPACT LOAD. The load resulting from moving machinery, elevators, craneways, vehicles and other similar forces and kinetic loads, pressure and possible surcharge from fixed or moving loads.
IMPORTANCE FACTOR, I. A factor that accounts for the degree of hazard to human life and damage to property.
INCAPABLE OF SELF-PRESERVATION. Persons who, because of age, physical limitations, mental limitations, chemical dependency or medical treatment, cannot respond as an individual to an emergency situation.
INCIDENT. An occurrence directly caused by construction or demolition activity or site conditions that result in one or more of the following:
   1.   A fatality to a member of the public;
   2.   Any type of injury to a member of the public;
   3.   A fatality to a worker;
   4.   An injury to a worker that requires transport by emergency medical services or requires immediate emergency care at a hospital or offsite medical clinic;
   5.   Any complete or partial structural collapse or material failure;
   6.   Any complete or partial collapse or failure of pedestrian protection, scaffolding, hoisting equipment, or material handling equipment; or
   7.   Any material fall exterior to the building or structure.
INCOMPATIBLE MATERIALS. Materials that, if mixed or combined, could explode, generate heat, gases or other byproducts, or react in such a way that are hazardous to life or property.
INDUSTRIAL ROPE ACCESS. The use of rope access equipment in which a person descends or ascends on a rope, or traverses along a rope, and in which the ropes are used as the primary means of support and positioning. Industrial rope access does not include window washing.
INERT GAS. A gas that is capable of reacting with other materials only under abnormal conditions such as high temperatures, pressures and similar extrinsic physical forces. Within the context of the code, inert gases do not exhibit either physical or health properties as defined (other than acting as a simple asphyxiant) or hazard properties other than those of a compressed gas. Some of the more common inert gases include argon, helium, krypton, neon, nitrogen and xenon.
INITIATING DEVICE. A system component that originates transmission of a change-of-state condition, such as in a smoke detector, manual fire alarm box or supervisory switch.
INSTALLING/INSTALLATION/INSTALL (SCAFFOLD). The initial installation or reinstallation of a scaffold at a site.
   Initial installation (scaffold). The initial assembly, set-up, or placement of a scaffold at a site.
   Reinstallation (scaffold). The addition, relocation, or removal of any part, component, or attachment to a scaffold at a site, including but not limited to counterweights, tie-backs, anchorages, or connections to the building or structure, that occurs subsequent to the initial installation, and which does not otherwise occur in an automated, automatic fashion, as part of the normal use of the scaffold.
INTENDED TO BE OCCUPIED AS A RESIDENCE. This refers to a dwelling unit or sleeping unit that can or will be used all or part of the time as the occupant's place of abode.
INTERIOR EXIT RAMP. An exit component that serves to meet one or more means of egress design requirements, such as required number of exits or exit access travel distance, and provides for a protected path of egress travel to the exit discharge or public way.
INTERIOR EXIT STAIRWAY. An exit component that serves to meet one or more means of egress design requirements, such as required number of exits or exit access travel distance, and provides for a protected path of egress travel to the exit discharge or public way.
INTERIOR FINISH. Interior finish includes interior wall and ceiling finish and interior floor finish.
INTERIOR FLOOR FINISH. The exposed floor surfaces of buildings including coverings applied over a finished floor or stair, including risers.
INTERIOR FLOOR-WALL BASE. Interior floor finish trim used to provide a functional or decorative border at the intersection of walls and floors.
INTERIOR SURFACES. Surfaces other than weather-exposed surfaces.
INTERIOR WALL AND CEILING FINISH. The exposed interior surfaces of buildings including, but not limited to: fixed or movable walls and partitions; toilet room privacy partitions; columns; ceilings; and interior wainscoting, paneling or other finish applied structurally or for decoration, acoustical correction, surface insulation, structural fire resistance or similar purposes, but not including trim.
INTERLAYMENT. A layer of felt or nonbituminous saturated felt not less than 18 inches (457 mm) wide, shingled between each course of a wood-shake roof covering.
INTUMESCENT FIRE-RESISTANT COATINGS. Thin film liquid mixture applied to substrates which expands into a protective foamed layer to provide fire-resistant protection of the substrates when exposed to flame or intense heat.
JIB. An extension attached to the boom point to provide added boom length for lifting specified loads. The jib may be in line with the boom or offset to various angles in the vertical plane of the boom.
JOINT. The opening in or between adjacent assemblies that is created due to building tolerances, or is designed to allow independent movement of the building in any plane caused by thermal, seismic, wind or any other loading.
JUMP (JUMPING or CLIMBING). The raising or lowering of a tower crane to a new working height. This can include, but is not limited to, the process of adding or removing mast or tower sections to equipment that has already been erected.
KEY ELEMENT. An element of the structural system, including its connections, that meets one or more of the following criteria:
   1.   An element which when lost, results in more than local collapse.
   2.   An element that braces a key element, the failure of which results in failure of the key element (further secondary elements need not be considered key elements).
   3.   An element whose tributary area exceeds 3,000 square feet (279 m 2 ) on a single level.
KITCHEN. A room with 80 square feet (7.4 m 2 ) or more of floor area that is intended, arranged, designed or used for cooking or warming of food.
KITCHENETTE. A space with less than 80 square feet (7.4 m 2 ) of floor area that is intended, arranged, designed or used for cooking or warming of food.
L RATING. The air leakage rating of a through-penetration firestop system or a fire-resistant joint system when tested in accordance with UL 1479 or UL 2079, respectively.
LABORATORY BUILDING. See Section 427.4.
LABORATORY CHEMICAL. See Section 427.4.
LABORATORY, NONPRODUCTION. See Section 427.4.
LABORATORY UNIT. See Section 427.4.
LAYERED (SOIL). Two or more distinctly different soil or rock types arranged in layers. Micaceous seams or weakened planes in rock or shale are considered layered.
LETTER OF MAP AMENDMENT (LOMA). See Section G201.1.2.
LETTER OF MAP REVISION BASED ON FILL (LOMR-F). See Section G201.1.2.
LETTER OF MAP REVISION (LOMR). See Section G201.1.2.
LIGHT DUTY SCAFFOLD. A supported scaffold capable of supporting loads of up to 25 pounds per square foot (122.05 kg/m 2 ), and not more than those imposed by workers and lightweight material, including but not limited to wood or paint.
LIGHT DUTY SIDEWALK SHED. A sidewalk shed designed to carry a live load of at least 150 pounds per square foot (732.3 kg/m 2 ).
LIGHT-DIFFUSING SYSTEM. Construction consisting in whole or in part of lenses, panels, grids or baffles made with light-transmitting plastics positioned below independently mounted electrical light sources, skylights or light-transmitting plastic roof panels. Lenses, panels, grids and baffles that are part of an electrical fixture shall not be considered as a light-diffusing system.
LIGHT-FRAME CONSTRUCTION. A type of construction whose vertical and horizontal structural elements are primarily formed by a system of repetitive wood or cold-formed steel framing members.
LIGHT-TRANSMITTING PLASTIC ROOF PANELS. Structural plastic panels other than skylights that are fastened to structural members, or panels or sheathing, and that are used as light-transmitting media in the plane of the roof.
LIGHT-TRANSMITTING PLASTIC WALL PANELS. Plastic materials that are fastened to structural members, or to structural panels or sheathing, and that are used as light-transmitting media in exterior walls.
LIMIT STATE. A condition beyond which a structure or member becomes unfit for service and is judged to be no longer useful for its intended function (serviceability limit state) or to be unsafe (strength limit state).
LIMITED AREA SPRINKLER SYSTEM. An automatic sprinkler system serving not more than 6 sprinkler heads on any single connection.
LIMITED SITE SAFETY TRAINING (SST) CARD. A card that is issued before the SST full compliance date, in a form and manner established by the department and that satisfies each of the following conditions:
   1.   Such card is issued by an SST provider to a person who submits an application to such provider demonstrating, in a form and manner established by the department, that such applicant satisfies the requirements of Item 1.1, 1.2 or 1.3:
      1.1.   Such applicant has successfully completed (i) an OSHA 10-hour class and (ii) 20 additional SST credits specified by the department, including eight SST credits relating to safeguarding against the dangers posed by falling workers and objects.
      1.2.   Such applicant has successfully completed an OSHA 30-hour class.
      1.3.   Such applicant has successfully completed a 100-hour training program.
   2.   If such applicant completed the training to comply with Item 1.1, 1.2 or 1.3 but did not complete such training within the five years preceding submission of such application, such applicant has, in the one-year period preceding submission of such application, completed at least eight SST credits specified by the department.
   3.   Such card is issued by an SST provider who does not require applicants to submit any information except for (i) the information necessary to establish that the requirements in Item 1 have been satisfied, as specified by the department, (ii) a photograph of the applicant and (iii) such additional information as the department may allow by rule.
   4.   Such card expires on the day before the SST full compliance date and is not renewable.
LIQUEFACTION. For granular soils, liquefaction is defined as the loss of shear strength in soils resulting from increased pore-water pressure and reduced effective stress that may develop as a result of cyclic loading during earthquakes. For cohesive soils with a plasticity index of less than 20, liquefaction is defined as any transient softening and increased cyclic shear strains that may occur during earthquakes.
LIQUID. A material that has a melting point that is equal to or less than 68°F (20°C) and a boiling point that is greater than 68°F (20°C) at 14.7 pounds per square inch absolute (psia) (101 kPa). When not otherwise identified, the term "liquid" includes both flammable and combustible liquids.
LIQUID STORAGE ROOM. A room classified as Group H-3 occupancy used for the storage of flammable or combustible liquids in an unopened condition.
LIQUID USE, DISPENSING AND MIXING ROOM. A room in which Class I, II and IIIA flammable or combustible liquids are used, dispensed or mixed in open containers.
LIVE LOAD. A load produced by the use and occupancy of the building or other structure and do not include construction or environmental loads such as wind load, snow load, rain load, earthquake load, flood load or dead load.
LIVE LOAD (ROOF). A load on a roof produced:
   1.   During maintenance by workers, equipment and materials;
   2.   During the life of the structure by movable objects such as planters or other small decorative appurtenances that are not occupancy related; or
   3.   By the use and occupancy of the roof such as for roof gardens or assembly areas.
LOAD AND RESISTANCE FACTOR DESIGN (LRFD). A method of proportioning structural members and their connections using load and resistance factors such that no applicable limit state is reached when the structure is subjected to appropriate load combinations. The term "LRFD" is used in the design of steel and wood structures.
LOAD BLOCK, LOWER. The assembly of hook or shackle, swivel, sheaves, pins, and frame suspended by the hoisting ropes.
LOAD BLOCK, UPPER. The assembly of shackle, swivel, sheaves, pins, and frame suspended from the boom point.
LOAD EFFECTS. Forces and deformations produced in structural members by the applied loads.
LOAD FACTOR. A factor that accounts for deviations of the actual load from the nominal load; for uncertainties in the analysis that transforms the load into a loud effect, and for the probability that more than one extreme load will occur simultaneously.
LOAD RATING CHART. A full and complete range of manufacturer's load ratings at all stated operating radii, boom angles, work areas, boom lengths and configurations, jib lengths and angles (or offset), as well as alternative ratings for use and nonuse of optional equipment, such as outriggers and extra counterweights, that affect ratings.
LOAD RATINGS. Crane and derrick ratings in pounds (kilograms) established by the manufacturer in accordance with standards set forth in rules promulgated by the commissioner.
LOAD (WORKING). The external load, in pounds (kilograms), applied to the crane or derrick, including the weight or auxiliary load attaching equipment, such as lower load blocks, shackles, and slings.
LOADS. Forces or other actions that result from the weight of building materials, occupants and their possessions, environmental effects, differential movement and restrained dimensional changes. Permanent loads are those loads in which variations over time are rare or of small magnitude, such as dead loads. All other loads are variable loads (see also "Nominal loads").
LOCAL COLLAPSE. Failure of a structural element that results in the collapse of areas being directly supported by that element and not extending vertically more than three stories.
LOT. A portion or parcel of land considered as a unit. 
LOT LINE. A line dividing one lot from another, or from a street or any public place.
LOT, TAX. A portion or parcel of land classified as such by the department of finance. Where a tax lot line shifts in a vertical plane, the commissioner shall determine the manner in which provisions of this code apply with respect to measurements to or from such tax lot lines, in order to protect public safety.
LOW ENERGY POWER-OPERATED DOOR. Swinging door that opens automatically upon an action by a pedestrian such as pressing a push plate or waving a hand in front of a sensor. The door closes automatically, and operates with decreased forces and decreased speeds (See "Power-assisted door" and "Power-operated door").
LOWER FLAMMABLE LIMIT (LFL). The minimum concentration of vapor in air at which propagation of flame will occur in the presence of an ignition source. The LFL is sometimes referred to as "LEL" or "lower explosive limit."
LOWEST FLOOR. The lowest floor of the lowest enclosed area, including crawl spaces and basements (for flood zone purposes).The lowest floor shall not include any wet floodproofed spaces usable solely for vehicle parking, building access, storage or crawl space, provided that such enclosure is not built so as to render the structure in violation of Appendix G, including that:
   1.    Such enclosure shall allow for the automatic entry and exit of floodwaters;
   2.    Such enclosure shall be constructed solely of flood-resistant materials and finishes;
   3.    Such enclosure shall have a floor elevation equal to or higher than the outside adjacent grade on at least one side; and
   4.    Such outside adjacent grade shall slope down, towards the source of flooding, providing positive drainage by gravity, thus preventing accumulations of water under or in the structure after the floodwaters recede without the use of pumps, pipes or drains.
MAILBOXES. Receptacles for the receipt of documents, packages or other deliverable matter. Mailboxes include, but are not limited to, post office boxes and receptacles provided by commercial mail-receiving agencies, apartment houses and schools.
MAIN WIND FORCE-RESISTING SYSTEM. An assemblage of structural elements assigned to provide support and stability for the overall structure. The system generally receives wind loading from more than one surface.
MAINTENANCE (SCAFFOLD). Regular or periodic upkeep as specified by the manufacturer to keep the scaffold, including all parts or components, in like new condition and safe working order, and that does not otherwise meet the definition of an installation, removal, or repair.
MAJOR BUILDING. An existing or proposed building 10 or more stories or 125 feet (38 100 mm) or more in height, or an existing or proposed building with a building footprint of 100,000 square feet (30 480 m 2 ) or more regardless of height, or an existing or proposed building so designated by the commissioner due to unique hazards associated with the construction or demolition of the structure.
MANUAL FIRE ALARM BOX. A manually operated device used to initiate an alarm signal.
MANUFACTURE DATE (Crane). For a particular crane, the earlier of the following dates:
   1.   The date the crane was originally manufactured for its intended purpose.
   2.   The date that the oldest major component of the crane was originally manufactured.
MANUFACTURED HOME. See Section G201.1.2.
MANUFACTURED HOME PARK OR SUBDIVISION. See Section G201.1.2.
MARKET VALUE OF STRUCTURE. See Section G201.1.2.
MARQUEE. A permanent roofed structure attached to and supported by the building and that projects into the public right-of-way.
MASONRY. A built-up construction or combination of building units or materials of clay, shale, concrete, glass, gypsum, stone or other approved units bonded together with or without mortar or grout or other accepted methods of joining.
   Glass unit masonry. Masonry composed of glass units bonded by mortar.
   Plain masonry. Masonry in which the tensile resistance of the masonry is taken into consideration and the effects of stresses in reinforcement are neglected.
   Reinforced masonry. Masonry construction in which reinforcement acting in conjunction with the masonry is used to resist forces.
   Solid masonry. Masonry consisting of solid masonry units laid contiguously with the joints between the units filled with mortar.
   Unreinforced (plain) masonry. Masonry in which the tensile resistance of masonry is taken into consideration and the resistance of the reinforcing steel, if present, is neglected.
MASONRY UNIT. Brick, tile, stone, glass block or concrete block conforming to the requirements specified in Section 2103.
   Hollow. A masonry unit whose net cross-sectional area in any plane parallel to the load-bearing surface is less than 75 percent of its gross cross-sectional area measured in the same plane.
   Solid. A masonry unit whose net cross-sectional area in every plane parallel to the load-bearing surface is 75 percent of more of its gross cross-sectional area measured in the same plane.
MASS CONCRETE. Any volume of concrete with dimensions large enough to require that measures be taken to cope with generation of heat from hydration of the cement and attendant volume change to minimize cracking, reduction of compressive strength, and/or delayed ettringite formation.
MAST CLIMBER. A powered device consisting of an elevating platform mounted on a base or chassis and mast, that when erected is capable of supporting personnel, material, equipment and tools on a deck or platform that is capable of traveling vertically in infinitely adjustable increments to reach the desired work level.
MASTIC FIRE-RESISTANT COATINGS. Liquid mixture applied to a substrate by brush, roller, spray or trowel that provides fire-resistant protection of a substrate when exposed to flame or intense heat.
MATERIAL HANDLING EQUIPMENT. Power or manually operated equipment that moves or transports material or personnel during the construction or demolition of a building or structure. Material handling equipment shall not include an elevator, hoisting equipment, mast climber, or scaffold.
MATERIAL HOIST (MATERIAL HOISTING EQUIPMENT). A power or manually operated platform, car, or cage, that (i) is temporarily installed at a construction or demolition site, (ii) moves vertically on guide members to raise or lower material, and (iii) is controlled from a point outside the conveyance.
MAXIMUM CONSIDERED EARTHQUAKE GEOMETRIC MEAN (MCEG) PEAK GROUND ACCELERATION. The most severe earthquake effects considered by this standard determined for geometric mean peak ground acceleration and without adjustment for targeted risk. The MCE G peak ground acceleration adjusted for site effects (PGA M ) is used in this standard for evaluation of liquefaction, lateral spreading, seismic settlements, and other soil-related issues. The PGA M values adjusted for site effects are provided in Table 1816.2.1 or can be derived from the site-specific procedures provided in Section 21.5 of ASCE 7.
MAXIMUM CONSIDERED EARTHQUAKE (MCE) GROUND MOTION. The most severe earthquake effects considered by this code more specifically defined in the terms, maximum considered earthquake geometric mean (MCE G ) peak ground acceleration and risk-targeted maximum considered earthquake (MCE R ) ground motion response acceleration.
MEAN ROOF HEIGHT. The average of the roof eave height and the height to the highest point on the roof surface, except that eave height shall be used for roof angle of less than or equal to 10 degrees (0.1745 rad).
MEANS OF EGRESS. A continuous and unobstructed path of vertical and horizontal egress travel from any occupied portion of a building or structure to a public way. A means of egress consists of three separate and distinct parts: the exit access, the exit and the exit discharge.
MECHANICAL-ACCESS OPEN PARKING GARAGE. Open parking garages employing parking machines, lifts, elevators or other mechanical device for vehicles moving from and to street level and in which public occupancy is prohibited above the street level.
MECHANICAL DEMOLITION EQUIPMENT. Mechanically driven or powered equipment that is utilized to physically demolish a building or structure, or elements of a building or structure, either within or exterior to the building or structure, or that is utilized to move debris or material within the building or structure. Mechanical demolition equipment shall not include mechanically driven or powered equipment that is utilized to move debris or material outside of the building or structure.
MECHANICAL EQUIPMENT SCREEN. A partially enclosed rooftop structure used to aesthetically conceal heating, ventilating and air conditioning (HVAC) electrical or mechanical equipment from view.
MECHANICAL SYSTEMS (STRUCTURAL). For the purposes of determining seismic loads in this code, mechanical systems shall also include fire protection, plumbing and fuel gas systems as specified therein.
MEDIUM DUTY SCAFFOLD. A supported scaffold capable of supporting loads of up to 50 pounds per square foot (244.1 kg/m 2 ), and not more than those imposed by workers and moderate material, including but not limited to brick and pipe.
MEMBRANE PENETRATION. A breach in one side of a floor-ceiling, roof-ceiling or wall assembly to accommodate an item installed into or passing through the breach.
MEMBRANE-COVERED CABLE STRUCTURE. A nonpressurized structure in which a mast and cable system provides support and tension to the membrane weather barrier and the membrane imparts stability to the structure.
MEMBRANE-COVERED FRAME STRUCTURE. A nonpressurized building wherein the structure is composed of a rigid framework to support a tensioned membrane that provides the weather barrier.
MEMBRANE-PENETRATION FIRESTOP. A material, device, or assemblage of specific materials or products that is designed, tested and fire-resistance rated to resist for a prescribed time period the passage of flame and heat through openings in a protective membrane in order to accommodate cables, cable trays, conduit, tubing, piping or similar items.
MEMBRANE-PENETRATION FIRESTOP SYSTEM. An assemblage consisting of a fire-resistance-rated floor-ceiling, roof-ceiling or wall assembly, one or more penetrating items installed into or passing through the breach in one side of the assembly and the materials or devices, or both, installed to resist the spread of fire into the assembly for a prescribed period of time.
MERCHANDISE PAD. A merchandise pad is an area for display of merchandise surrounded by aisles, permanent fixtures or walls. Merchandise pads contain elements such as nonfixed and moveable fixtures, cases, racks, counters and partitions from which customers browse or shop.
METAL COMPOSITE MATERIAL (MCM). A factory-manufactured panel consisting of metal skins bonded to both faces of a plastic core.
METAL COMPOSITE MATERIAL (MCM) SYSTEM. An exterior wall covering fabricated using MCM in a specific assembly including joints, seams, attachments, substrate, framing and other details as appropriate to a particular design.
METAL ROOF PANEL. An interlocking metal sheet having a minimum installed weather exposure of 3 square feet (0.279 m 2 ) per sheet.
METAL ROOF SHINGLE. An interlocking metal sheet having an installed weather exposure less than 3 square feet (0.279 m 2 ) per sheet.
MEZZANINE. An intermediate level or levels between the floor and ceiling of any story in accordance with Section 505.
MICROPILE. A micropile is a drilled and grouted deep foundation element with a diameter that measures 5 inches (127 mm) to 14 inches (356 mm) that develops its load-carrying capacity by means of a bond zone in soil (also commonly known as a minipile).
MINERAL BOARD. A rigid felted thermal insulation board consisting of either felted mineral fiber or cellular beads of expanded aggregate formed into flat rectangular units.
MINERAL FIBER. Insulation composed principally of fibers manufactured from rock, slag or glass, with or without binders. 
MINERAL WOOL. Synthetic vitreous fiber insulation made by melting predominantly igneous rock or furnace slag, and other inorganic materials, and then physically forming the melt into fibers.
MINOR ALTERATIONS. See Section 105.4.2* of the Administrative Code.
* Editor's note: As set forth in L.L. 2021/126; correct reference should be Section 28-105.4.2.
MOBILE CRANE. A crane equipped with rubber-tired wheels or crawler treads for travel. The definition of mobile crane shall include, but is not limited, to a commercial truck mounted crane, crawler crane, wheel mounted crane (multiple control stations) or wheel mounted crane (single control station). The definition of mobile crane shall not include a truck mounted crane or a self-erecting tower crane.
MOBILE SCAFFOLD. A powered or unpowered, portable, caster, track or wheel-mounted supported scaffold.
MODIFIED BITUMEN ROOF COVERING. One or more layers of polymer-modified asphalt sheets. The sheet materials shall be fully adhered or mechanically attached to the substrate or held in place with an approved ballast layer.
MOIST (SOIL). A condition in which a soil looks and feels damp. Moist cohesive soil can easily be shaped into a ball and rolled into small diameter threads before crumbling. Moist granular soil that contains some cohesive material will exhibit signs of cohesion between particles.
MONOPOLE SIGN. A ground sign wholly supported by a single pole structure.
MORTAR. A mixture consisting of cementitious materials, fine aggregates, water, with or without admixtures, that is used to construct unit masonry assemblies.
MORTAR, SURFACE-BONDING. A mixture to bond concrete masonry units that contains hydraulic cement, glass fiber reinforcement with or without inorganic fillers or organic modifiers and water.
MULTILEVEL ASSEMBLY SEATING. Seating that is arranged in distinct levels where each level is comprised of either multiple rows, or single row of box seats accessed from a separate level.
MULTIPLE-STATION ALARM DEVICE. Two or more single-station alarm devices that can be interconnected such that actuation of one causes all integral or separate audible alarms to operate. A multiple-station alarm device can consist of one single-station alarm device having connections to other detectors or to a manual fire alarm box.
MULTIPLE-STATION SMOKE ALARM. Two or more single-station alarm devices that are capable of interconnection such that actuation of one causes the appropriate alarm signal to operate in all interconnected alarms and not connected to a fire alarm system.
MULTIPOINT ADJUSTABLE SUSPENDED SCAFFOLD. A suspended scaffold consisting of a platform(s) that is suspended by more than two ropes from overhead supports and equipped with a means to raise and lower the platform to the desired work levels.
MULTISTORY UNIT. A dwelling unit or sleeping unit with habitable space located on more than one story.
NAILING, BOUNDARY. A special nailing pattern required by design at the boundaries of diaphragms.
NAILING, EDGE. A special nailing pattern required by design at the edges of each panel within the assembly of a diaphragm or shear wall.
NAILING, FIELD. Nailing required between the sheathing panels and framing members at locations other than boundary nailing and edge nailing.
NATIONAL GEODETIC VERTICAL DATUM (NGVD). The national vertical datum standard established in 1929; used as a reference for establishing elevations within a floodplain.
NATURALLY DURABLE WOOD. The heartwood of the following species except for the occasional piece with corner sapwood, provided 90 percent or more of the width of each side on which it occurs is heartwood:
   Decay resistant. Redwood, cedar, black locust and black walnut.
   Termite resistant. Redwood, Alaska yellow cedar, Eastern red cedar and Western red cedar.
NEW CONSTRUCTION. See Section G201.1.2.
NOMINAL LOADS. The magnitudes of the loads specified in Chapter 16 (dead, live, soil, wind, snow, rain, flood and earthquake).
NOMINAL SIZE (LUMBER). The commercial size designation of width and depth, in standard sawn lumber and glued-laminated lumber grades; somewhat larger than the standard net size of dressed lumber, in accordance with DOC PS 20 for sawn lumber and with the ANSI/AWC NDS for glued-laminated lumber.
NONCOMBUSTIBLE MEMBRANE STRUCTURE. A membrane structure in which the membrane and all component parts of the structure are noncombustible.
NONRESIDENTIAL (FOR FLOOD ZONE PURPOSES). A building or structure that either:
   1.   Contains no space classified in Group I-1, R-1, R-2 or R-3, and contains no space that is accessory, as such term is defined in the New York City Zoning Resolution, to any Group I-1, R-1, R-2 or R-3 occupancy; or
   2.   Contains such space(s), but also contains space at or below the DFE that is not accessory, as such term is defined in the New York City Zoning Resolution, to a Group I-1, R-1, R-2 or R-3 occupancy.
NORMAL TEMPERATURE AND PRESSURE (NTP). A temperature of 70°F (21°C) and a pressure of 1 atmosphere (14.7 psia (101 kPa)).
NORTH AMERICAN VERTICAL DATUM (NAVD). The national vertical datum standard established in 1988, used as a reference for establishing elevations within a floodplain.
NOSING. The leading edge of treads of stairs and of landings at the top of stairway flights.
NOTATIONS. For Chapter 16, see Section 1602.1.
NOTATIONS. For Chapter 21, see Section 2102.1.
NOTIFICATION ZONE. See "Zone, notification."
NURSING HOMES. See Section 308.2.2.
OCCUPANT LOAD. The number of persons for which the means of egress of a building or portion thereof is designed.
OCCUPANT SENSOR. A device that detects the presence or absence of people within an area and causes lighting, equipment, or appliances to be regulated accordingly.
OCCUPIABLE SPACE. A room or enclosed space, other than a habitable space, designed for human occupancy or use in which individuals may remain for a period of time for rest, amusement, treatment, education, dining, shopping, employment, labor or other similar purposes.
OPEN-ENDED CORRIDOR. An interior corridor that is open on each end and connects to an exterior stairway or ramp at each end with no intervening doors or separation from the corridor.
OPEN EXTERIOR SPACE. See Section 1002.1.2.
OPEN PARKING GARAGE. A structure or portion of a structure with the openings as described in Section 406.5.2 that is used for the parking or storage of private motor vehicles as described in Section 406.5.3.
OPEN PARKING LOT. An exterior space with surfacing at grade used for the storage or sale of more than four motor vehicles, including but not limited to parking lots, motor vehicles sales lots, and accessory open parking spaces.
OPEN SYSTEM. The use of a solid or liquid hazardous material in equipment or a vessel or system that remains open during normal operation such that vapors are emitted during the operation of such equipment, vessel or system and the material is exposed to the atmosphere during such operation. Examples of open systems for solids and liquids include dispensing from or into open beakers or containers, dip tank and plating tank operations.
ORDINARY REPAIRS. See Section 105.4.2* of the Administrative Code.
* Editor's note: As set forth in L.L. 2021/126; correct reference should be Section 28-105.4.2.
ORGANIC PEROXIDE. An organic compound having a double oxygen or peroxy (-O-O-) in its chemical structure. Organic peroxides can present an explosion hazard (detonation or deflagration), can be shock sensitive, or can be susceptible to decomposition into various unstable compounds over an extended period of time and are classified as follows based upon their hazardous properties:
   Class I. Organic peroxides that are capable of deflagration but not detonation.
   Class II. Organic peroxides that burn very rapidly and that pose a moderate reactivity hazard.
   Class III. Organic peroxides that burn rapidly and that pose a moderate reactivity hazard.
   Class IV. Organic peroxides that burn in the same manner as ordinary combustibles and that pose a minimal reactivity hazard.
   Class V. Organic peroxides that burn with less intensity than ordinary combustibles or do not sustain combustion and that pose no reactivity hazard.
   Unclassified detonable. Organic peroxides that are capable of detonation and pose an extremely high explosion hazard through rapid explosive decomposition.
ORTHOGONAL. To be in two horizontal directions, at 90 degrees (1.57 rad) to each other.
OSHA. The United States Department of Labor Occupational Safety and Health Administration.
OSHA 10-HOUR CLASS. A class that includes 10 or more hours in construction industry safety and health that is intended for workers and satisfies the following conditions:
   1.   Such class is (i) approved by OSHA and conducted in accordance with the OSHA outreach training program or (ii) an equivalent 10 or more hour class approved by the department.
   2.   Such class consists of in-person training, actively proctored online training or, if such training is conducted before the effective date of the local law that added this definition, online training.
OSHA 30-HOUR CLASS. A class that includes 30 or more hours in construction industry safety and health that is intended for supervisors and satisfies the following conditions:
   1.   Such class is (i) approved by OSHA and conducted in accordance with the OSHA outreach training program or (ii) an equivalent 30 or more hour class approved by the department.
   2.   Such class consists of in-person training, actively proctored online training or, if such training is conducted before the effective date of the local law that added this definition, online training.
OTHER STRUCTURES. Structures, other than buildings, for which loads are specified in Chapter 16.
OUTRIGGER (CRANE). Extendable or fixed members attached to the mounting base that rest on supports at the outer ends used to support the crane.
OUTRIGGER (SCAFFOLD). The structural member of a supported scaffold used to increase the base width of a scaffold in order to provide support for and increased stability of the scaffold.
OUTRIGGER BEAM (THRUSTOUT). The structural member of a suspended scaffold or outrigger scaffold that provides support for the scaffold by extending the scaffold point of attachment to a point out and away from the structure or building.
OUTRIGGER SCAFFOLD. A supported scaffold consisting of a platform resting on outrigger beams (thrustouts) projecting beyond the wall or face of the building or structure, the inboard ends of which are secured inside the building or structure.
OXIDIZER. A material that readily yields oxygen or other oxidizing gas or that readily reacts to promote or initiate combustion of combustible materials, and if heated or contaminated can result in vigorous self-sustained decomposition, classified as follows:
   Class 4. An oxidizer that can undergo an explosive reaction due to contamination or exposure to thermal or physical shock and causes a severe increase in the burning rate of combustible materials with which it comes into contact.
   Class 3. An oxidizer that causes a severe increase in the burning rate of combustible materials with which it comes in contact.
   Class 2. An oxidizer that causes a moderate increase in the burning rate of combustible materials with which it comes in contact.
   Class 1. An oxidizer that causes a readily measurable increase in the burning rate of combustible materials with which it comes in contact, but less than a moderate increase.
OXIDIZING GAS. A gas that can support and accelerate combustion of other materials more than air does.
PANEL (PART OF A STRUCTURE). The selection of a floor, wall or roof comprised between the supporting frame of two adjacent rows of columns and girders or column bands of floor or roof construction.
PANIC HARDWARE. A door-latching assembly incorporating a device that releases the latch upon the application of a force in the direction of egress travel.
PARKING GARAGE. A structure or portion of a structure, other than a private garage or carport, used for the parking or storage of motor vehicles.
PARTICLEBOARD. A generic term for a panel primarily composed of cellulosic materials (usually wood), generally in the form of discrete pieces or particles, as distinguished from fibers. The cellulosic material is combined with synthetic resin or other suitable bonding system by a process in which the interparticle bond is created by the bonding system under heat and pressure.
PATIENT CARE AREA (FOR FLOOD ZONE PURPOSES). Any space meeting the following conditions:
   1.   The space is located within a building or structure, or portion thereof, that is classified in Group I-2; and
   2.   The space is primarily used for the provision of medical services to persons, including, but not limited to, consultation, evaluation, monitoring and treatment services.
      Exceptions: The following spaces shall not be considered patient care areas (for flood zone purposes):
         1.   "Emergency rooms or departments" as defined in 10 NYCRR 700.2(a)(2) and
         2.   Spaces primarily used for the provision of medical services identified in 10 NYCRR 703.6(c)(2)(i).
PENETRATION FIRESTOP. A through-penetration firestop or a membrane-penetration firestop.
PENTHOUSE. An enclosed rooftop structure that is designed or used for human occupancy.
PERFORMANCE CATEGORY. A designation of wood structural panels as related to the panel performance used in Chapter 23.
PERMANENT PRESTRESSED ROCK AND SOIL ANCHORS. Corrosion-protected tendons consisting of bars or strands installed in drilled and grouted holes in soil or rock that are stressed.
PERSONAL CARE SERVICE. The care of residents who do not require chronic or convalescent medical or nursing care. Personal care involves responsibility for the safety of the resident while inside the building.
PERSONNEL HOIST. A mechanism and its hoistway that is (i) temporarily installed at a construction or demolition site, and (ii) is equipped with a car that moves vertically on guide members to raise or lower workers or workers and materials.
PHOTOSENSOR. A device that detects the presence of visible light.
PHOTOLUMINESCENT. Having the property of emitting light that continues for a length of time after excitation by visible or invisible light has been removed.
PHOTOVOLTAIC MODULE. A complete, environmentally protected unit consisting of solar cells, optics and other components, exclusive of tracker, designed to generate DC power when exposed to sunlight.
PHOTOVOLTAIC PANEL. A collection of modules mechanically fastened together, wired and designed to provide a field-installable unit.
PHOTOVOLTAIC PANEL SYSTEM. A system that incorporates discrete photovoltaic panels that converts solar radiation into electricity, including rack support systems.
PHOTOVOLTAIC SHINGLES. A roof covering resembling shingles that incorporates photovoltaic modules.
PHYSICAL HAZARD. A chemical for which there is evidence that it is a combustible liquid, compressed gas, cryogenic explosive, flammable gas, flammable liquid, flammable solid, organic peroxide, oxidizer, pyrophoric or unstable (reactive) or water-reactive material.
PHYSIOLOGICAL WARNING THRESHOLD LEVEL. A concentration of air-borne contaminants, normally expressed in parts per million (ppm) or milligrams per cubic meter (mg/m 3 ), that represents the concentration at which persons can sense the presence of the contaminant due to odor, irritation or other quick-acting physiological response. When used in conjunction with the permissible exposure limit (PEL), the physiological warning threshold levels are those consistent with the classification system used to establish the PEL. See the definition of "Permissible exposure limit (PEL)" in the New York City Fire Code.
PIER FOUNDATION. A pier foundation is a shallow foundation element of masonry or cast-in-place concrete construction. Piers are relatively short in comparison to their width, with lengths less than or equal to 12 times the least horizontal dimension of the pier. Piers derive their load-carrying capacity from end bearing on soil or rock.
PILE DRIVER. Equipment that is configured to drive, hammer, press, or vibrate piles into the earth ("pile drive").
PINRAIL. A rail on or above a stage through which belaying pins are inserted and to which lines are fastened.
PLACE OF ASSEMBLY. A building, structure, or portion thereof, excluding a dwelling unit, but including outdoor spaces, used or intended to be used for the gathering of a group of persons for purposes such as civic, social, or religious functions, recreation, food or drink consumption, educational or instructional purposes, awaiting transportation, or similar group activities when such use requires a place of assembly Certificate of Operation pursuant to Section 303.7.
PLASTIC, APPROVED. Any thermoplastic, thermosetting or reinforced thermosetting plastic material that conforms to combustibility classifications specified in the section applicable to the application and plastic type.
PLASTIC, COMPOSITE. A generic designation that refers to wood/plastic composites and plastic lumber.
PLASTIC GLAZING. Plastic materials that are glazed or set in frame or sash and not held by mechanical fasteners that pass through the glazing material.
PLASTIC LUMBER. A manufactured product made primarily of plastic materials (filled or unfilled) that is generally rectangular in cross section.
PLASTIC (SOIL). A property of a soil that allows the soil to be deformed or molded without cracking, or appreciable volume change.
PLATFORM (SPECIAL USE). See Section 410.2.2.
PLATFORM. A work surface elevated above lower levels. Platforms can be constructed using individual wood planks, fabricated planks or fabricated decks.
POLE SIGN. A sign wholly supported by a sign structure in the ground.
POLYPROPYLENE SIDING. A shaped material, made principally from polypropylene homopolymer or copolymer, which in some cases contains fillers or reinforcements, that is used to clad exterior walls of buildings.
PORCELAIN TILE. Tile that conforms to the requirements of ANSI 137.1.3 for ceramic tile having an absorption of 0.5 percent or less in accordance with ANSI 137.4.1-Class Table and ANSI 137.1.6.1 Allowable Properties by Tile Type - Table 10.
POSITIVE ROOF DRAINAGE. The drainage condition in which consideration has been made for all loading deflections of the roof deck, including ponding instability, and additional slope has been provided to ensure drainage of the roof within 48 hours of precipitation.
POST-CONSTRUCTION STORMWATER MANAGEMENT FACILITY. See Section 28-104.11.1 of the Administrative Code.
POST-FIRE SMOKE PURGE SYSTEM. A mechanical or natural ventilation system intended to move smoke from the smoke zone to the exterior of the building. Such systems are intended for the timely restoration of operations and overhaul activities once a fire is extinguished. Post-fire smoke purge systems are not intended or designed to be life safety systems.
POST-FIRM DEVELOPMENT. See Section G201.1.2.
POST-FIRM STRUCTURE. See Section G201.1.2.
POWER BUGGIES. An automotive vehicle designed or used for the transportation of materials on or about construction or demolition sites. It shall not include automobiles, motor trucks, general purpose tractors, or excavating or similar material handling machinery.
POWER-ASSISTED DOOR. Swinging door that opens by reduced pushing or pulling force on the door-operating hardware. The door closes automatically after the pushing or pulling force is released and functions with decreased forces. See "Low-energy power-operated door" and "Power-operated door".
POWER-OPERATED DOOR. Swinging, sliding, or folding door that opens automatically when approached by a pedestrian or opens automatically upon an action by a pedestrian. The door closes automatically and includes provisions such as presence sensors to prevent entrapment. See "Low-energy power-operated door" and "Power-assisted door".
PRE-FIRM DEVELOPMENT. See Section G201.1.2.
PRE-FIRM STRUCTURE. See Section G201.1.2.
PREFABRICATED WOOD I-JOIST. Structural member manufactured using sawn or structural composite lumber flanges and wood structural panel webs bonded together with exterior exposure adhesives, which forms an "I" cross-sectional shape.
PRESIGNAL SYSTEM. A fire alarm system having a feature that allows initial fire alarm signals to sound in a constantly attended central location and for which a human action is subsequently required to achieve a general alarm, or a feature that allows the control equipment to delay the general alarm by more than 1 minute after the start of the alarm processing.
PRESSURIZATION. Creation and maintenance of pressure levels in zones of a building, including elevator shafts and stairwells, that are higher than the pressure level at the smoke source, such pressure levels being produced by positive pressures of a supply of uncontaminated air; by exhausting air and smoke at the smoke source; or by a combination of these methods.
PRESTRESSED MASONRY. Masonry in which internal stresses have been introduced to counteract potential tensile stresses in masonry resulting from applied loads.
PRIMARY FUNCTION AREAS. An area of a building or facility containing a major activity for which the building or facility is intended is a primary function area.
PRIMARY STRUCTURAL FRAME. The primary structural frame shall include all of the following structural members:
   1.   The columns;
   2.   Structural members having direct connections to the columns, including girders, beams, trusses and spandrels;
   3.   Members of the floor construction and roof construction having direct connections to the columns; and
   4.   Bracing members that are essential to the vertical stability of the primary structural frame under gravity loading, shall be considered part of the primary structural frame whether or not the bracing member carries gravity loads.
PRIVATE GARAGE. An enclosed structure or portion of a structure, accessory to a Group R-2 or R-3 occupancy, used for the parking or storage of passenger motor vehicles. Such facility shall not exceed 650 square feet (60 m 2 ) in area and one story in height.
PROJECTING SIGN. A sign other than a wall sign that projects from and is supported by a wall of a building or structure.
PROSCENIUM WALL. The wall that separates the stage from the auditorium or assembly seating area.
PUBLIC ENTRANCE. An entrance that is not a service entrance.
PUBLIC WAY. A street, alley or other parcel of land open to the outside air leading to a street that has been deeded, dedicated or otherwise permanently appropriated to the public for public use and which has a clear width and height of not less than 10 feet (3048 mm).
PUBLIC-USE AREAS. Interior or exterior rooms or spaces that are made available to the general public.
PYROPHORIC MATERIAL. A material with an auto-ignition temperature in air, at or below a temperature of 130°F (54°C).
PYROTECHNIC MATERIAL. A chemical mixture consisting predominantly of solids that, upon ignition, are capable of producing a controlled, self-sustaining, and self-contained exothermic reaction, that functions without external oxygen, resulting in a visible or audible effect by combustion, deflagration, or detonation.
QUALIFIED PERSON. A person who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated his or her ability to solve or resolve problems related to the subject matter, the work, or the project.
RADIANT BARRIER. A material having a low-emittance surface of 0.1 or less installed in building assemblies.
RAMP. A walking surface that has a running slope steeper than one unit vertical in 20 units horizontal (5-percent slope).
RAMP-ACCESS OPEN PARKING GARAGE. Open parking garages employing a series of continuously rising floors or a series of interconnecting ramps between floors permitting the movement of vehicles under their own power from and to the street level.
RECLAIMED ASPHALT PAVEMENT. Asphalt pavement that has been processed for reuse in asphaltic concrete.
RECORD DRAWINGS. Drawings ("as builts") that document the location of all devices, appliances, wiring sequences, wiring methods and connections of the components of a fire alarm system as installed.
RECREATIONAL VEHICLE. See Section G201.1.2.
REFLECTIVE PLASTIC CORE FOIL INSULATION. An insulation material packaged in rolls, that is less than 1/2 inch (12.7 mm) thick, with at least one exterior low emittance surface (0.1 or less) and a core material containing voids or cells.
REFUGE AREA. A floor area to which egress is made through a horizontal exit.
RELIGIOUS WORSHIP, PLACE OF. A building or portion thereof intended for the performance of religious services.
REMOVING/REMOVAL/REMOVE (SCAFFOLD). The final process of taking apart a scaffold in a specific sequence and removing it from the site.
REPAIR (SCAFFOLD). Work performed to restore a scaffold, or any part or component, to like new condition and safe working order following decay, wear, or damage. The definition of repair shall also include the replacement of a part or component.
REPLACEMENT (SCAFFOLD). A repair involving the exchange or substitution of one part or component with another identical or similar part or component in order to restore a scaffold, or any part or component, to like new condition and safe working order following decay, wear, or damage.
REROOFING. The process of recovering or replacing an existing roof covering. See "Roof recover" and "Roof replacement."
RESIDENTIAL AIRCRAFT HANGAR. An accessory building less than 2,000 square feet (186 m 2 ) and 20 feet (6096 mm) in building height constructed on a one- or two-family property where aircraft are stored. Such use will be considered as a residential accessory use incidental to the dwelling.
RESIDENTIAL CARE/ASSISTED LIVING FACILITIES. A building or part thereof housing persons, on a 24-hour basis, who because of age, mental disability or other reasons, live in a supervised residential environment that provides personal care services. The occupants are capable of self-preservation and are capable of responding to an emergency situation without physical assistance from staff. This classification shall include, but not be limited to, the following: residential board and care facilities, assisted living facilities, halfway houses, congregate care facilities, social rehabilitation facilities, alcohol and drug abuse rehabilitation centers and convalescent facilities.
RESIDENTIAL (FOR FLOOD ZONE PURPOSES). A building or structure containing any space that is either:
   1.   Classified in Group I-1, R-1, R-2, or R-3; or
   2.   Accessory, as such term is defined in the  New York City Zoning Resolution , to any Group I-1, R-1, R-2, or R-3 occupancy.
   Exception: Such a building or structure shall be considered nonresidential (for flood zone purposes) when also containing space at or below the DFE that is not accessory, as such term is defined in the  New York City Zoning Resolution , to a Group I-1, R-1, R-2, or R-3 occupancy.
RESISTANCE FACTOR. A factor that accounts for deviations of the actual strength from the nominal strength and the manner of consequences of failure (also called "strength reduction factor").
RESPONSE RATIO. The ratio of an ultimate response quantity (e.g., deflection) to its value at yield.
RESTRICTED ENTRANCE. An entrance that is made available for public use but on a controlled basis, and that is not a service entrance.
RETAINING WALL. A wall that resists lateral or other forces caused by soil, rock, water or other materials, thereby limiting lateral displacement and the movement of the supported materials. Basement walls and vault walls that are parts of buildings and underground structures, including but not limited to utility vault structures, tunnels, transit stations, and swimming pools, are not considered retaining walls.
RETRACTABLE AWNING. A retractable awning is a cover with a frame that retracts against a building or other structure to which it is entirely supported.
RIM BOARD. In light-frame construction, a full depth structural member designed to transfer horizontal (shear) and vertical (compression) loads, provide attachment for diaphragm sheathing, siding and exterior deck ledgers, and provide lateral support at the ends of floor or roof joists or rafters.
RISK CATEGORY. A categorization of buildings and other structures for determination of flood, wind, snow, ice and earthquake loads based on the risk associated with unacceptable performance.
RISK-TARGETED MAXIMUM CONSIDERED EARTHQUAKE (MCER) GROUND MOTION RESPONSE ACCELERATIONS. The most severe earthquake effects considered by this standard determined for the orientation that results in the largest maximum response for horizontal ground motions and with adjustment for targeted risk. The MCER  Ground Motion values can be determined from general procedure in Section 1613.3.3 of this code or can be derived from the site specific procedures provided in Sections 21.1 and 21.2 of ASCE 7.
ROPE. A continuous line of material comprised of a number of twisted or braided strands of fiber (natural or synthetic) or metal wire.
ROOF ASSEMBLY. A system designed to provide weather protection and resistance to design loads. The system consists of a roof covering and roof deck or a single component serving as both the roof covering and the roof deck. A roof assembly includes the roof deck, vapor retarder, substrate or thermal barrier, insulation and roof covering.
ROOF COVERING. The covering applied to the roof deck for weather resistance, fire classification or appearance.
ROOF COVERING SYSTEM. See "Roof assembly."
ROOF DECK. The flat or sloped surface constructed on top of the exterior walls of a building or other supports for the purpose of enclosing the story below, or sheltering an area, to protect it from the elements, not including its supporting members or vertical supports.
ROOF RECOVER. The process of installing an additional roof covering over a prepared existing roof covering without removing the existing roof covering.
ROOF REPAIR. Reconstruction or renewal of any part of an existing roof for the purposes of its maintenance.
ROOF REPLACEMENT. The process of removing the existing roof covering, repairing any damaged substrate and installing a new roof covering.
ROOF SIGN. A sign erected on or above a roof or parapet of a building or structure.
ROOF VENTILATION. The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from, attics, cathedral ceilings or other enclosed spaces over which a roof assembly is installed.
ROOFTOP STRUCTURE. An enclosed or unenclosed structure on or above the roof of any part of a building.
ROOMING HOUSE. A dwelling (i) which was originally erected as single- or two-family private dwelling pursuant to the  New York City Building Code  in effect prior to December 6, 1968, (ii) which is a "Class B converted dwelling" as such term is defined in the  New York City Housing Maintenance Code , and (iii) which has more than half of its habitable rooms as sleeping units. The creation of or conversion to a rooming house shall be limited by Section 27-2077 of the  New York City Housing Maintenance Code .
ROTATING TELEHANDLER. A telehandler whose boom is mounted on a rotating or slewing superstructure.
ROTATION. The angle, measured at the ends of a member, whose tangent is equal to the deflection of the member at midspan divided by half the length of the member.
RUNBACK STRUCTURE. A temporary system of hoistway landing runways, vertical supports and horizontal diaphragms designed to bridge between the hoistway and the parent structure and to transmit both vertical and horizontal loads to the supporting structure and/or foundation.
RUNNING BOND. The placement of masonry units such that head joints in successive courses are horizontally offset at least one-quarter the unit length.
SAFE AREA. See Section 1002.1.2.
SAFETY NETTING SYSTEM (SAFETY NETTING). Debris or structural nets, installed vertically or horizontally, along with all supports, components, and connections.
   Horizontal safety netting. A safety netting system, installed horizontally, consisting of structural netting lined with debris netting.
   Vertical safety netting. A safety netting system, installed vertically, consisting of debris netting.
SALLYPORT. See Section 408.1.1.
SAND DUNES. Naturally occurring accumulations of sand in ridges or mounds landward of a beach.
SCAFFOLD. Any temporary elevated platform and its supporting structure (including points of anchorage) used for supporting workers or workers and material, including but not limited to supported scaffolds, suspended scaffolds, and mobile scaffolds.
SCAFFOLD CONTROLLING ENTITY. The contractor or other entity that exercises responsibility for the site where the scaffold is located.
SCISSOR STAIRWAY. Two interlocking stairways providing two separate paths of egress located within one stairwell enclosure.
SCUPPER. An opening in a wall or parapet that allows water to drain from a roof.
SEATING SECTION. See Section 1002.1.2.
SECONDARY MEMBERS. The following structural members shall be considered secondary members and not part of the primary structural frame:
   1.   Structural members not having direct connections to the columns;
   2.   Members of the floor construction not having direct connections to the columns; and
   3.   Bracing members other than those that are part of the primary structural frame.
SEISMIC DESIGN CATEGORY. A classification assigned to a structure based on its risk category and the severity of the design earthquake ground motion at the site.
SEISMIC FORCE-RESISTING SYSTEM. The part of the structural system that has been considered in the design to provide the required resistance to the prescribed seismic forces.
SELF-CLOSING. As applied to a fire door or other opening, means equipped with a listed and approved device that will ensure closing after having been opened.
SELF-ERECTING TOWER CRANE. A tower crane that adjusts its operating radius by means of a trolley traversing a jib and that; (i) possesses a vertical or nearly vertical tower or mast that is bottom slewing and mounted on fixed, traveling, or mobile bases; and (ii) is capable of folding and unfolding to facilitate transit from site to site with minimal assembly.
SELF-LUMINOUS. Illuminated by a self-contained power source, other than batteries, and operated independently of external power sources.
SELF-SERVICE STORAGE FACILITY. Real property designed and used for the purpose of renting or leasing individual storage spaces to customers for the purpose of storing and removing personal property on a self-service basis.
SERVICE CORRIDOR. A fully enclosed passage other than one designated as a required means of egress, through which HPM can be moved during handling.
SERVICE ENTRANCE. An entrance solely for delivery of goods or services.
SERVICES. Includes, but is not limited to, toilet rooms, drinking fountains, public telephones and food.
SHADED X-ZONE. The land in the floodplain delineated as subject to a 0.2 percent or greater chance of flooding, but less than one percent chance of flooding, in any given year. Such areas are designated on the Flood Insurance Rate Map (FIRM) as shaded X-Zones.
SHAFT. An enclosed space extending through one or more stories of a building, connecting vertical openings in successive floors, or floors and roof.
SHAFT ENCLOSURE. The walls or construction forming the boundaries of a shaft.
SHALLOW FOUNDATION. A shallow foundation is an individual or strip footing, a mat foundation, a slab-on-grade foundation or a similar foundation element.
SHEAR WALL. A wall designed to resist lateral forces parallel to the plane of a wall.
   Shear wall, perforated. A wood structural panel sheathed wall with openings, that has not been specifically designed and detailed for force transfer around openings.
   Shear wall segment, perforated. A section of shear wall with full-height sheathing that meets the height-to-width ratio limits of Section 4.3.4 of AWC SDPWS.
SHORE, MULTI-STAGE. Formwork assemblies on a single level comprised of discontinuous vertical post elements stacked on top of each other.
SIDELITES. Fixed transparent panels that form part of or are immediately adjacent to and within 6 feet (1829 mm) horizontally of the vertical edge of an opening in which transparent doors are located. A sidelite shall consist of transparent material in which the transparent area above a reference line 18 inches (457 mm) above the adjacent ground, floor or equivalent surface is 80 percent or more of the remaining area of the panel above such reference line.
SIGN. Any letter, figure, character, mark, plane, point, marquee sign, design, poster, pictorial, picture, stroke, stripe, line, trademark, reading matter or illuminated service, which shall be constructed, placed, attached, painted, erected, fastened or manufactured in any manner whatsoever, so that the same shall be used for the attraction of the public to anyplace, subject, person, firm, corporation, public performance, article, machine or merchandise, whatsoever, which is displayed in any manner outdoors. Every sign shall be classified and conform to the requirements of that classification as set forth in this code.
SIGN STRUCTURE. Any structure that supports or is capable of supporting a sign as defined in this code.
SINGLE-PLY MEMBRANE. A roofing membrane that is field applied using one layer of membrane material (either homogeneous or composite) rather than multiple layers.
SINGLE-POINT ADJUSTABLE SUSPENDED SCAFFOLD. A suspended scaffold consisting of a platform suspended by one rope from an overhead support and equipped with means to permit the movement of the platform to desired work levels.
SINGLE-STATION SMOKE ALARM. An assembly incorporating the detector, the control equipment and the alarm-sounding device in one unit, operated from a power supply either in the unit or obtained at the point of installation.
SITE. A parcel of land bounded by a lot line or a designated portion of a public right-of-way.
SITE CLASS. A classification assigned to a site based on the types of soils present and their engineering properties as defined in Section 1613.3.2.
SITE COEFFICIENTS. The values of, Fa , and, Fv , indicated in Tables 1613.3.3(1) and 1613.3.3(2), respectively.
SITE-FABRICATED STRETCH SYSTEM. A system, fabricated on site and intended for acoustical, tackable or aesthetic purposes, that is comprised of three elements: (a) a frame (constructed of plastic, wood, metal or other material) used to hold fabric in place, (b) a core material (infill, with the correct properties for the application), and (c) an outside layer, comprised of a textile, fabric or vinyl, that is stretched taut and held in place by tension or mechanical fasteners via the frame.
SITE SAFETY TRAINING (SST) CARD. A card that is issued in a form and manner established by the department and that satisfies each of the following conditions:
   1.   Such card is issued by an SST provider to a person who submits an application to such provider demonstrating, in a form and manner established by the department, that such applicant satisfies the requirements of Item 1.1, 1.2 or 1.3:
      1.1.   Such applicant has successfully completed (i) an OSHA 10-hour class and (ii) 30-45 additional SST credits specified by the department, including eight SST credits relating to safeguarding against the dangers posed by falling workers and objects.
      1.2.   Such applicant has successfully completed (i) an OSHA 30-hour class and (ii) 10-25 additional SST credits specified by the department, including eight SST credits relating to safeguarding against the dangers posed by falling workers and objects.
      1.3.   Such applicant has successfully completed a 100-hour training program.
   2.   If such applicant completed the training to comply with Item 1.1, 1.2 or 1.3 but did not complete such training within the five years preceding submission of such application, such applicant has, in the one-year period preceding submission of such application, completed at least eight SST credits specified by the department.
   3.   Such card is issued by an SST provider who does not require applicants to submit any information except for (i) the information necessary to establish that the requirements in Item 1 have been satisfied, as specified by the department, (ii) a photograph of the applicant and (iii) such additional information as the department may allow by rule.
   4.   Such card expires five years after issuance and is renewable upon a showing by the applicant that such applicant has, in the one-year period preceding submission of such renewal application, successfully completed eight SST credits specified by the department.
SITE SAFETY TRAINING (SST) CREDIT. One hour of training that satisfies each of the requirements of Item 1, 2 and 3:
   1.   Such training relates to a topic identified by department rule.
   2.   If such training is conducted on or after the effective date of the local law that added this definition, such training is in-person training or actively proctored online training.
   3.   If such training is conducted on or after March 1, 2018, such training is conducted by an SST provider.
SITE SAFETY TRAINING (SST) FULL COMPLIANCE DATE. March 1, 2021.
SITE SAFETY TRAINING (SST) PROVIDER. An entity that satisfies the requirements of Items 1 and 2:
   1.   Such entity satisfies the conditions of Item 1.1, 1.2, 1.3 or 1.4:
      1.1.   Such entity is a not-for-profit organization with a history of at least three years of experience in providing construction-related workforce development, construction-related education or site safety training, which may be demonstrated by submitting training logs to the department or in a form and manner otherwise determined by the department, and training offered by such entity is offered by a person who has (i) successfully completed all applicable OSHA or department requirements for conducting OSHA 10-hour classes and OSHA 30-hour classes and is authorized to conduct such classes and (ii) if such person is conducting training for SST credits other than training that is part of an OSHA 10-hour class or OSHA 30-hour class, such person demonstrates sufficient knowledge of this chapter in a form and manner established by the department. Such entity shall not be required to demonstrate any professional standing, approval, licensure, accreditation or certification, including approval, licensure, accreditation or certification pursuant to paragraph (2) of subdivision d of section 105-03 of subchapter E of chapter 100 of title 1 of the rules of the city of New York, as in effect on January 1, 2018, beyond showing that such entity and a person offering training on behalf of such entity satisfy the requirements set forth in the preceding sentence. Where the department provides content, developed in accordance with department-approved course requirements, for the delivery of SST credits, such entity shall deliver SST credits in accordance with such content. Where the department does not provide content for the delivery of SST credits, such entity shall be responsible for the development of content in accordance with department-approved course requirements. Such content and the delivery of such content may be subject to approval or audit by the department.
      1.2.   Such entity is providing training through a 100-hour training program.
      1.3.   Such entity has been approved by the department to conduct a 40-hour course approved by the department pursuant to Article 402 of Chapter 4 of Title 28 of the Administrative Code.
      1.4.   The department may establish by rule additional ways for an entity to satisfy the requirements of this Item 1. If the department elects to promulgate such rules, an entity shall be deemed to satisfy this Item 1 if such entity satisfies the requirements set forth in such rules or if such entity satisfies the requirements set forth in Item 1.1, 1.2 or 1.3.
   2.   On and after the SST full compliance date, such entity has certified to the department that such entity satisfies at least one of the following conditions:
      2.1.   Such entity has a language access plan for training that relates to SST credits such entity offers and such plan complies with requirements established by an agency or office designated by the mayor.
      2.2.   Such entity satisfies each of the following conditions:
         2.2.1.   Such entity is able to provide instruction in a language that students understand.
         2.2.2.   If a student's vocabulary is limited, such entity will accommodate that limitation.
         2.2.3.   A person offering training on behalf of such entity is fluent in the training language or will use translators or interpreters and any such translators or interpreters will have a background in occupational safety and health.
SITE SAFETY TRAINING (SST) SECOND COMPLIANCE DATE. December 1, 2019, or, if the department publishes a finding by September 1, 2019, that there is insufficient capacity to provide the training required by Section 3321 of this code to the workers who would need such training, a later date established by the department, provided that such date is not later than June 1, 2020.
SITE SAFETY TRAINING (SST) SUPERVISOR CARD. A card that satisfies each of the following conditions:
   1.   Such card is issued in a form and manner established by the department to a person who demonstrates that such person has an SST card and has successfully completed an OSHA 30-hour class.
   2.   Such card expires five years after issuance and is renewable upon a showing by the applicant that such applicant has, in the one-year period preceding such submission of such renewal application, successfully completed 16 SST credits specified by the department.
SITE SAFETY TRAINING (SST) TASK FORCE. The task force established pursuant to Section 28-103.28 of the Administrative Code.
SKYLIGHT, UNIT. A factory-assembled, glazed fenestration unit, containing one panel of glazing material that allows for natural lighting through an opening in the roof assembly while preserving the weather-resistant barrier of the roof.
SKYLIGHTS AND SLOPED GLAZING. Glass or other transparent or translucent glazing material installed at a slope of 15 degrees (0.26 rad) or more from vertical. Glazing material in skylights, including unit skylights, solariums, sunrooms, roofs and sloped walls, are included in this definition.
SLEEPING UNIT. A dwelling unit, which may contain either toilet or kitchen facilities but not both. Any sleeping unit housing more than one family shall also be classified as a congregate living unit. The creation of or conversion to sleeping units shall be limited by Section 27-2077 of the New York City Housing Maintenance Code.
SLEEPING UNIT (ACCESSIBILITY). As used in Chapter 11 and Appendix E, a room or space in which people sleep, which can also include permanent provisions for living, eating, and either sanitation or kitchen facilities but not both. Such rooms and spaces that are also part of a dwelling unit are not sleeping units.
SMALL WIND TURBINE. A turbine with a swept area smaller than 200 m 2 that generates a voltage below 1,000 V (AC) or 1,500 V (DC).
SMALL WIND TURBINE TOWER. A structure that supports a small wind turbine.
SMOKE. Air-borne solid and liquid particulates and gases evolved when a material undergoes pyrolysis or combustion, including the quality of air that is entrained or otherwise mixed into the mass.
SMOKE ALARM. A single- or multiple-station alarm responsive to smoke and not connected to a fire alarm system. See "Multiple-station smoke alarm" and "Single-station smoke alarm."
SMOKE BARRIER. A continuous membrane, either vertical or horizontal, such as a wall, floor, or ceiling assembly, that is designed and constructed in accordance with Section 709 to restrict the movement of smoke.
SMOKE COMPARTMENT. A space within a building enclosed by smoke barriers on all sides, including the top and bottom.
SMOKE CONTROL MODE. A predefined operational configuration of a system or device for the purpose of smoke control.
SMOKE CONTROL SYSTEM, MECHANICAL. An engineered system that includes all methods that can be used singly or in combination to modify smoke movement.
SMOKE CONTROL SYSTEM, PASSIVE. A system of smoke barriers arranged to limit the migration of smoke.
SMOKE CONTROL ZONE. A space within a building enclosed by smoke barriers that is part of a smoke control system.
SMOKE DAMPER. See "Dampers, Types of."
SMOKE DETECTOR. A listed device that senses visible or invisible particles of combustion or smoke.
SMOKE PARTITION. A continuous vertical assembly that is designed and constructed to restrict the movement of smoke and is not generally required to have a fire-resistance rating in accordance with Section 710.
SMOKE-DEVELOPED INDEX. A comparative measure, expressed as a dimensionless number, derived from measurements of smoke obscuration versus time for a material tested in accordance with ASTM E 84.
SMOKEPROOF ENCLOSURE. An exit stairway, ramp or passageway designed and constructed so that the movement of the products of combustion produced by a fire occurring in any part of the building into the enclosure is limited.
SMOKE-PROTECTED ASSEMBLY SEATING. Seating served by means of egress that is not subject to smoke accumulation within or under a structure.
SOIL AND FOUNDATION WORK (SOIL OR FOUNDATION WORK). Excavation, fill, grading, augering, boring, or drilling, whether in soil or rock; or the installation or removal of foundations, piles, underpinning, sheeting, shoring, or supports of excavation.
SOLID. A material that has a melting point, decomposes or sublimates at a temperature greater than 68°F (20°C).
SPECIAL AMUSEMENT BUILDING. A special amusement building is any temporary or permanent building or portion thereof that is occupied for amusement, entertainment or educational purposes and that contains a device or system that conveys passengers or provides a walkway along, around or over a course in any direction so arranged that the means of egress path is not readily apparent due to visual or audio distractions or is intentionally confounded or is not readily available because of the nature of the attraction or more of conveyance through the building or structure.
SPECIAL FLOOD HAZARD AREA. Land in the floodplain subject to a 1% or greater chance of flooding in any given year; area delineated on the Flood Insurance Rate Map as Zone A, AE, A1-30, A99, AR, AO, AH, V, VO, VE, or V1-30. Such areas include A-Zones, Coastal A-Zones, and V-Zones.
SPECIAL INSPECTION, CONTINUOUS. The observation of work requiring special inspection by a special inspector who is continuously present in the area where the work is being performed while the work is being performed.
SPECIAL INSPECTION, PERIODIC. The intermittent observation of work requiring special inspection by a special inspector who is present in the area where the work has been or is being performed and at the completion of the work. All work requiring special inspection shall remain accessible and exposed until approved by the special inspector.
SPECIFIC LOCAL LOAD. A load applied to a structural element or structural system as specified in Section 1617.6.
SPECIFIC LOCAL RESISTANCE METHOD. A design approach that accounts for extreme event loads by providing sufficient strength for elements that may fail. In a specific local resistance design, key elements are designed for specific local loads as required by Section 1617.
SPECIFIED COMPRESSIVE STRENGTH OF MASONRY, f'm. Minimum compressive strength, expressed as force per unit of net cross-sectional area, required of the masonry used in construction by the approved construction documents, and upon which the project design is based. Whenever the quantity f'm is under the radical sign, the square root of numerical value only is intended and the result has units of pounds per square inch (psi) (Mpa).
SPLICE. The result of a factory and/or field method of joining or connecting two or more lengths of a fire-resistant joint system into a continuous entity.
SPRAYED FIRE-RESISTANT MATERIALS. Cementitious or fibrous materials that are sprayed to provide fire-resistant protection of the substrates.
STABLE (ROCK). A condition in which natural solid mineral matter (rock) can be excavated with vertical sides and remain intact while exposed.
STACK EFFECT. The vertical airflow within buildings caused by the temperature-created density differences between the building interior and exterior or between two interior spaces.
STAGE. A space within a building utilized for entertainment or presentations, which includes overhead hanging curtains, drops, scenery or stage effects other than lighting and sound.
STAIR. A change in elevation, consisting of two or more risers.
STAIR TOWER (SCAFFOLD STAIRWAY/TOWER). A tower comprised of scaffold components and that contains internal stairway units and rest platforms. These towers are used to provide access to scaffold platforms and other elevated points such as floors and roofs.
STAIRWAY. One or more flights of stairs, either exterior or interior, with the necessary landings and platforms connecting them, to form a continuous and uninterrupted passage from one level to another.
STAIRWAY, SPIRAL. A stairway having a closed circular form in its plan view with uniform section-shaped treads attached to and radiating from a minimum-diameter-supporting column.
STANDARD CUBIC FEET (SCF). Cubic feet of gas at normal temperature and pressure (NTP).
STANDARD GUARDRAIL SYSTEM (SCAFFOLD). See "Guardrail system (scaffold)."
STAND-OFF BRACKET (SUSPENDED SCAFFOLD). A rigid member that attaches to a cornice hook (c-hook) in order to provide additional outreach from the face of the parapet or wall.
STANDPIPE SYSTEM. Piping, installed in a building or structure, that serves to supply water to hose connections at one or more locations in a building or structure, for firefighting purposes.
STANDPIPE SYSTEM, CLASSES OF. Standpipe classes are as follows:
   Class I system. A system providing 2 1/2-inch (64 mm) hose connections to supply water for use by the Fire Department and those trained in handling heavy fire streams.
   Class II system. A system providing 1 1/2-inch (38 mm) hose stations to supply water for use primarily by the building occupants or by the Fire Department during initial response.
   Class III system. A system providing 1 1/2-inch (38 mm) hose stations to supply water for use by building occupants and 2 1/2-inch (64 mm) hose connections to supply a larger volume of water for use by the Fire Department and those trained in handling heavy fire streams.
STANDPIPE SYSTEM, TYPES OF. Standpipe system types are as follows:
   Automatic dry. A dry standpipe system, normally filled with pressurized air, that is arranged through the use of a device, such as dry pipe valve, to admit water into the system piping automatically upon the opening of a hose valve. The water supply for an automatic dry standpipe system shall be capable of supplying the system demand.
   Automatic wet. A wet standpipe system that has a water supply that is capable of supplying the system demand automatically.
   Manual dry. A dry standpipe system that does not have a permanent water supply attached to the system. Manual dry standpipe systems require water from a Fire Department pumper to be pumped into the system through the Fire Department connection in order to meet the system demand.
   Manual wet. A wet standpipe system connected to a water supply for the purpose of maintaining water within the system but that does not have a water supply capable of delivering the system demand attached to the system. Manual-wet standpipe systems require water from a Fire Department pumper to be pumped into the system in order to meet the system demand.
   Semiautomatic dry. A dry standpipe system that is arranged through the use of a device, such as a deluge valve, to admit water into the system piping upon activation of a remote control device location at a hose connection. A remote control activation device shall be provided at each hose connection. The water supply for a semiautomatic dry standpipe system shall be capable of supplying the system demand.
START OF CONSTRUCTION. See Section G201.1.2.
STEEL CONSTRUCTION, COLD-FORMED. That type of construction made up entirely or in part of steel structural members cold formed to shape from sheet or strip steel such as roof deck, floor and wall panels, studs, floor joists, roof joists and other structural elements.
STEEL ELEMENT, STRUCTURAL. Any steel structural member of a building or structure consisting of rolled shapes, pipe, hollow structural sections, plates, bars, sheets, rods or steel castings other than cold-formed steel, or steel joist members.
STEEL JOIST. Any steel structural member of a building or structure made of hot-rolled or cold-formed solid or open-web sections, or riveted or welded bars, strip or sheet steel members, or slotted and expanded, or otherwise deformed rolled sections.
STEEP SLOPE. A roof slope greater than two units vertical in 12 units horizontal (17-percent slope).
STONE MASONRY. Masonry composed of field, quarried or cast stone units bonded by mortar.
STORAGE CABINET. See Section 427.4.
STORAGE, HAZARDOUS MATERIALS. The keeping, retention or leaving of hazardous materials in closed containers, tanks, cylinders, or similar vessels; or vessels supplying operations through closed connections to the vessel.
STORAGE ROOM. See Section 427.4.
STORM SHELTER. See Section 423.2.
   Community storm shelter. See Section 423.2.
   Residential storm shelter. See Section 423.2.
STORMWATER CONSTRUCTION PERMIT. See Section 28-104.11.1 of the Administrative Code.
STORY. That portion of a building included between the upper surface of a floor and the upper surface of the floor or roof next above (also see "Basement" and "Mezzanine"). It is measured as the vertical distance from top to top of two successive tiers of beams or finished floor surfaces and, for the topmost story, from the top of the floor finish to the top of the ceiling joists or, where there is not a ceiling, to the top of the roof rafters.
STORY ABOVE GRADE PLANE. Any story having its finished floor surface entirely above grade plane, except that a basement shall also be considered a story above grade plane (see "Story" and "Basement").
STREET. A thoroughfare, including sidewalks and roadways, dedicated or devoted to public use by legal mapping or other lawful means, or a public way.
STREET FLOOR. A floor, usually the principal entrance floor, that is not more than one-half story above or below grade at the location from which egress is provided to the street.
STREET LINE. A lot line separating a street from other land.
STRENGTH DESIGN. A method of proportioning structural members such that the computed forces produced in the members by factored loads do not exceed the member design strength (also called "load and resistance factor design" (LRFD)). The term "strength design" is used in the design of concrete and masonry structural elements.
STRENGTH.
   Design strength. Nominal strength multiplied by a strength reduction factor.
   Nominal strength. Strength of a member or cross-section calculated in accordance with these provisions before application of any strength-reduction factors.
   Required strength. Strength of a member or cross-section required to resist factored loads.
STRENGTH, NOMINAL. The capacity of a structure or member to resist the effects of loads, as determined by computations using specified material strengths and dimensions and equations derived from accepted principles of structural mechanics or by field tests or laboratory tests of scaled models, allowing for modelling effects and differences between laboratory and field conditions.
STRENGTH, REQUIRED. Strength of a member, cross section or connection required to resist factored loads or related internal moments and forces in such combinations as stipulated by these provisions.
STRIPPING OPERATIONS. Removal on the floor of any parts of the concrete formwork including shoring, bracing and other supports.
STRUCTURAL COMPOSITE LUMBER. Structural member manufactured using wood elements bonded together with exterior adhesives. Examples of structural composite lumber are:
   Laminated strand lumber (LSL). A composite of wood strand elements with wood fibers primarily oriented along the length of the member, where the least dimension of the wood strand elements is 0.10 inch (2.54 mm) or less and their average lengths not less than 150 times the least dimension of the wood strand elements.
   Laminated veneer lumber (LVL). A composite of wood veneer sheet elements with wood fibers primarily oriented along the length of the member, where the veneer element thicknesses are 0.25 inches (6.4 mm) or less.
   Oriented strand lumber (OSL). A composite of wood strand elements with wood fibers primarily oriented along the length of the member, where the least dimension of the wood strand elements is 0.10 inch (2.54 mm) or less and their average lengths not less than 75 times and less than 150 times the least dimension of the strand elements.
   Parallel strand lumber (PSL). A composite of wood strand elements with wood fibers primarily oriented along the length of the member where the least dimension of the wood strand elements is 0.25 inches (6.4 mm) or less and their average lengths not less than 300 times the least dimension of the wood strand elements.
STRUCTURAL GLUED-LAMINATED TIMBER. An engineered, stress-rated product of a timber laminating plant, comprised of assemblies of specially selected and prepared wood laminations in which the grain of all laminations is approximately parallel longitudinally and the laminations are bonded with adhesives.
STRUCTURAL NET (STRUCTURAL NETTING). A system of nets capable of complying with the prototype test described in ANSI A10.11.
SUBMERGED SOIL. Soil which is underwater or is free seeping.
SUBSTANTIAL DAMAGE. Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred.
SUBSTANTIAL IMPROVEMENT. Any repair, reconstruction, rehabilitation, addition or improvement of a building or structure, the cost of which equals or exceeds 50 percent of the market value of the structure before the improvement or repair is started. If the structure has sustained substantial damage, any repairs are considered substantial improvement regardless of the actual repair work performed. The term does not, however, include either:
   1.   Any project for improvement of a building required to correct pre-FIRM health, sanitary or safety code violations identified by the commissioner, the Fire Commissioner, the Commissioner of Housing Preservation and Development, or the Commissioner of Health and Mental Hygiene, and that are the minimum necessary to assure safe living conditions; or
   2.   Any alteration of a historic structure provided that the alteration will not preclude the structure's continued designation as a historic structure.
SUN CONTROL DEVICE. An architectural projection that provides protection against solar radiation entering a building through glazed areas and is supported by the building to which it is attached. Sun control device includes, but is not limited to, a fixed, retractable or rotating sun control device. A fixed sun control device has no moving parts and is typically composed of horizontal overhangs or vertical fins. A retractable sun control device extends or retracts, and in the extended position casts a shadow on designated portions of the building. A rotating sun control device may be of fixed or adjustable length and pivots at its base. Sun control device shall not include awnings and canopies. 
SUNROOM. A one-story structure attached to a building with a glazing area in excess of 40 percent of the gross area of the structure's exterior walls and roof.
SUPERINTENDENT OF CONSTRUCTION. See Chapter 1 of Title 28 of the Administrative Code.
SUPERSTRUCTURE. The rotating upper frame structure of the machine and the operating machinery mounted thereon.
SUPERVISING STATION. A facility that receives signals from protected premises' fire alarm systems and at which personnel are in attendance at all times to respond to these signals.
   Supervising station, central. A supervising station that is listed and approved by the Fire Department for central station service.
   Supervising station, proprietary. A supervising station under the same ownership as the protected premises' fire alarm system(s) that it supervises (monitors) and to which alarm, supervisory, or trouble signals are received and where personnel are in attendance at all times to supervise operation and investigate signals.
   Supervising station, remote. A supervising station to which alarm, supervisory, or trouble signals or any combination of those signals emanating from protected premises' fire alarm systems are received and where personnel are in attendance at all times to respond.
SUPERVISORY SERVICE. The service required to monitor performance of guard tours and the operative condition of fixed suppression systems or other systems for the protection of life and property.
SUPERVISORY SIGNAL. A signal indicating the need for action in connection with the supervision of guard tours, fire suppression systems or equipment, fire alarm systems, or the maintenance features of related systems.
SUPERVISORY SIGNAL-INITIATING DEVICE. An initiation device, such as a valve supervisory switch, water-level indicator or low-air pressure switch on a dry-pipe sprinkler system, whose change of state signals an off-normal condition and its restoration to normal of a fire protection or life safety system, or a need for action in connection with the supervision of guard tours, fire suppression systems or equipment, fire alarm systems, or the maintenance features of related systems.
SUPPORTED SCAFFOLD. One or more platforms supported by outrigger beams, brackets, poles, legs, uprights, posts, frames, including prefabricated frames that are mechanized but not motorized, or any similar rigid support, including back structures connecting hoistways to buildings, and including structures where sidewalk protection is constructed as an integral part of the apparatus.
SUSCEPTIBLE BAY. A roof or portion thereof with:
   1.   A slope less than 1/4-inch per 1 foot (0.0208 rad); or
   2.   On which water is impounded, in whole or in part, and the secondary drainage system is functional but the primary drainage system is blocked.
   A roof surface with a slope of 1/4-inch per 1 foot (0.0208 rad) or greater towards points of free drainage is not a susceptible bay.
SUSPENDED SCAFFOLD. One or more platforms suspended by ropes or other means from an overhead structure.
SUSPENDED SCAFFOLD FOREMAN. An individual, male or female, designated by and working under the direct and continuing supervision of a licensed master or special rigger, or a licensed master or special sign hanger, in accordance with the rules of the department.
SUSTAINABLE ROOFING ZONE. Areas of a roof assembly where a solar photovoltaic electricity generating system, a green roof system, or a combination thereof, is installed.
SWIMMING POOL. Any indoor or outdoor swimming, wading, spa, or special-purpose pool.
   Exceptions:
      1.   Portable, freestanding wading pools containing water less than 24 inches (610 mm) in depth.
      2.   Float tanks or relaxation tanks sized for use by one person at a time.
      3.   Pools used for religious purposes.
      4.   Spa pools used for prescribed medical therapy or rehabilitation and under medical supervision.
SWIMMING POOL, PRIVATE. A swimming pool that is accessory to a one- or two-family dwelling, or to a single-dwelling unit of a multiple dwelling, and that is solely for the use of the occupants for noncommercial purposes.
SWIMMING POOL, PUBLIC. A swimming pool that is not a private swimming pool. Public swimming pools include swimming pools that are accessory to bathing establishments as such term is defined in the New York City Health Code, whether owned or operated by city agencies, or commercial interests or private entities, including, but not limited to, public or private schools, corporations, hotels, motels, camps, apartment houses, condominiums, country clubs, gymnasia and health establishments.
SWING. Rotation of the superstructure for movement of loads in a horizontal direction about the axis of rotation.
T RATING. The time period that the penetration firestop system, including the penetrating item, limits the maximum temperature rise to 325°F (163°C) above its initial temperature through the penetration on the nonfire side when tested in accordance with ASTM E 814 or UL 1479.
TECHNICAL PRODUCTION AREA. Open elevated areas or spaces intended for entertainment technicians to walk on and occupy for servicing and operating entertainment technology systems and equipment. Galleries, including fly and lighting galleries, gridirons, catwalks, and similar areas are designed for these purposes.
TELEHANDLER. A machine that consists of a powered chassis onto which is mounted an extendable boom. The outer end of the boom can be fitted with various lifting or manipulative devices, including but not limited to pallet forks.
TEMPORARY CONSTRUCTION INSTALLATIONS. Installations that are not part of the permanent structure and that are installed to facilitate construction or demolition work, and are intended to be taken apart or removed after a limited period following their installation. Such installations include, but are not limited to, scaffolds, sidewalk sheds, fences, tower cranes, run back structures, and similar construction and demolition related installations.
TEMPORARY SIGN. A sign, with display area 500 square feet (46.5 m 2 ) or less, erected for a period of 30 days or less.
TEMPORARY SITE SAFETY TRAINING (SST) CARD. A card that is issued in a form and manner established by the department and that satisfies each of the following conditions:
   1.   Such card is issued by an SST provider to a person who demonstrates that such person has successfully completed an OSHA 10-hour class and who is a new entrant to the construction or demolition work force as determined by such provider pursuant to department rules.
   2.   Such card expires six months after issuance and is not renewable.
TEMPORARY STRUCTURES. Tents, grandstands, platforms, reviewing stands, outdoor bandstands, stages, sculptures, and similar miscellaneous structures erected for a limited period.
TENABLE ENVIRONMENT. An environment in which the concentration and location of smoke is limited or otherwise restricted to allow for ready evaluation through the space.
TENSILE MEMBRANE STRUCTURE. A membrane structure having a shape that is determined by tension in the membrane and in the geometry of the support structure. Typically, the structure consists of both flexible elements (e.g. membrane and cables), non-flexible elements (e.g. struts, masts beams and arches), and the anchorage (e.g. supports and foundations). This includes frame supported tensile membrane structures.
TENT. A nonpressurized membrane structure of a fabric weather barrier supported by poles and guys, in which the fabric weather barrier does not impart stability to the structure. Tents need not be fully enclosed on the sides.
THERMAL ISOLATION. Physical and space conditioning separation from conditioned space(s). The conditioned space(s) shall be controlled as separate zones for heating and cooling or conditioned by separate equipment.
THERMOPLASTIC MATERIAL. A plastic material that is capable of being repeatedly softened by increase of temperature and hardened by decrease of temperature.
THERMOSETTING MATERIAL. A plastic material that is capable of being changed into a substantially nonreformable product when cured.
THROUGH-PENETRATION. A breach in both sides of a floor, floor-ceiling or wall assembly to accommodate an item passing through the breaches.
THROUGH-PENETRATION FIRESTOP SYSTEM. An assemblage consisting of a fire-resistance-rated floor, floor-ceiling, or wall assembly, one or more penetrating items passing through the breaches in both sides of the assembly and the materials or devices, or both, installed to resist the spread of fire through the assembly for a prescribed period of time.
TIE-DOWN (HOLD-DOWN). A device used to resist uplift of the chords of shear walls.
TIE, WALL. Metal connector that connects wythes of masonry walls together.
TILE, STRUCTURAL CLAY. A hollow masonry unit composed of burned clay, shale, fire clay or mixture thereof, and having parallel cells.
TIRES, BULK STORAGE OF. Storage of tires where the area available for storage exceeds 20,000 cubic feet (566 m 3 ).
TOOL. See "Equipment."
TOWER CRANE. A crane that utilizes a vertical mast or tower to support a working boom (jib) in an elevated position. Loads are suspended from the working boom. While the working boom may be of the fixed type (horizontal or angled) or have luffing capability, it can always rotate to swing loads, either by rotating on the top of the tower (top slewing) or by the rotation of the tower (bottom slewing). The tower base may be fixed in one location or ballasted and moveable between locations. The definition of a tower crane shall include a climber crane. The definition of a tower crane shall not include mobile cranes that are configured with luffing jib and/or tower attachments.
TOWNHOUSE. A single-family dwelling constructed in a group of three or more attached units in which each unit extends from the foundation to roof and with open space on at least two sides.
TOXIC MATERIAL. A chemical that is lethal at the following doses or concentrations:
   1.   A chemical that has a median lethal dose (LD 50 ) of more than 50 milligrams per 1 kilogram, but not more than 500 milligrams per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each; or
   2.   A chemical that has a median lethal dose (LD 50 ) of more than 200 milligrams per 1 kilogram but not more than 1,000 milligrams per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between 2 and 3 kilograms each; or
   3.   A chemical that has a median lethal concentration (LD 50 ) in air of more than 200 parts per million but not more than 2,000 parts per million by volume of gas or vapor, or more than 2 milligrams per liter but not more than 20 milligrams per liter of mist, fume or dust, when administered by continuous inhalation for 1 hour (or less if death occurs within 1 hour) to albino rats weighing between 200 and 300 grams each.
   Exception: For purposes of this code, chlorine shall be classified as a highly toxic material.
TRANSIENT. Occupancy of a dwelling unit or sleeping unit for less than 30 days.
TRANSIENT AIRCRAFT. Aircraft based at another location and that is at the transient location for not more than 90 days.
TRANSIENT LODGING. A building, facility or portion thereof, excluding inpatient medical care facilities and long-term care facilities, that contains one or more dwelling units or sleeping units. Examples of transient lodging include, but are not limited to, resorts, group homes, hotels, motels, dormitories, homeless shelters, halfway houses and social service lodging.
TRANSIT. The moving or transporting of a crane from one jobsite to another.
TRANSPARENT. The property of a material which is not opaque and through which objects lying beyond are clearly visible.
TRANSPARENT DOOR. A door, manually or power actuated, fabricated of transparent material, in which the transparent area above a reference line 18 inches (457 mm) above the bottom edge of the door is 80 percent or more of the remaining area of the door above such reference line.
TRANSPARENT SAFETY GLAZING MATERIALS. Materials which will clearly transmit light and also minimize the possibility of cutting or piercing injuries resulting from breakage of the material. Materials covered by this definition include laminated glass, heat-toughened glass, case-hardened glass or chemically tempered glass), wired glass, and plastic glazing.
TRAVEL. The function of the machine moving under its own power from one location to another on a jobsite.
TREATED WOOD. Wood products that are conditioned to enhance fire-retardant or preservative properties.
   Fire-retardant-treated wood. Wood products that, when impregnated with chemicals by a pressure process or other means during manufacture, exhibit reduced surface-burning characteristics and resist propagation of fire.
   Preservative-treated wood. Wood products that, conditioned with chemicals by a pressure process or other means, exhibit reduced susceptibility to damage by moisture, mold, fungi, insects or marine borers.
TRENCH. A narrow excavation (in relation to its length) made below the surface of the ground. In general, the depth is greater than the width, but the width of a trench (measured at the bottom) is not greater than 15 feet (4572 mm). If forms or other structures are installed or constructed in an excavation so as to reduce the dimension measured from the forms or structure to the side of the excavation to 15 feet (4572 mm) or less (measured at the bottom of the excavation), the excavation is also considered to be a trench.
TRIM. Picture molds, chair rails, baseboards, handrails, door and window frames and similar decorative or protective materials used in fixed applications.
TROUBLE SIGNAL. A signal initiated by the fire alarm system or device indicative of a fault in a monitored circuit or component.
TWO-POINT SUSPENDED SCAFFOLD (SWING STAGE). A suspended scaffold consisting of a platform supported by hangers (stirrups) suspended by two ropes from overhead supports and equipped with means to permit the raising and lowering of the platform to desired working levels.
TYPE A SOIL. Cohesive soils with an unconfined compressive strength of 1.5 ton per square foot (tsf) (144 kPa) or greater. Examples of cohesive soils are: clay, silty clay, sandy clay, clay loam and, in some cases, silty clay loam and sandy clay loam. Cemented soils such as caliche and hardpan are also considered Type A. However, no soil is Type A if:
   (i)   The soil is fissured;
   (ii)   The soil is subject to vibration from heavy traffic, pile driving, or similar effects;
   (iii)   The soil has been previously disturbed;
   (iv)   The soil is part of a sloped, layered system where the layers dip into the excavation on a slope of four horizontal to one vertical (4H:1V) or greater; or
   (v)   The material is subject to other factors that would require it to be classified as a less stable material.
TYPE B SOIL. Soils that meet one of the following:
   (i)   Cohesive soil with an unconfined compressive strength greater than 0.5 tsf (48 kPa) but less than 1.5 tsf (144 kPa);
   (ii)   Granular cohesionless soils including: angular gravel (similar to crushed rock), silt, silt loam, sandy loam and, in some cases, silty clay loam and sandy clay loam;
   (iii)   Previously disturbed soils except those which would otherwise be classed as Type C soil;
   (iv)   Soil that meets the unconfined compressive strength or cementation requirements for Type A, but is fissured or subject to vibration;
   (v)   Dry rock that is not stable; or
   (vi)   Material that is part of a sloped, layered system where the layers dip into the excavation on a slope less steep than four horizontal to one vertical (4H:1V), but only if the material would otherwise be classified as Type B.
TYPE B UNIT. A dwelling unit or sleeping unit designed and constructed for accessibility in accordance with this code and the provisions for Type B units in ICC A117.1, consistent with the design and construction requirements of the federal Fair Housing Act.
TYPE B+NYC UNIT. A dwelling unit or sleeping unit designed and constructed for accessibility in accordance with this code and Section 1004 (Type B Units) of ICC A117.1, except as modified by Sections 1107.2.1 through 1107.2.8 of this code.
TYPE C SOIL. Soils that meet one of the following:
   (i)   Cohesive soil with an unconfined compressive strength of 0.5 tsf (48kPa) or less;
   (ii)   Granular soils including gravel, sand, and loamy sand;
   (iii)   Submerged soil or soil from which water is freely seeping;
   (iv)   Submerged rock that is not stable, or
   (v)   Material in a sloped, layered system where the layers dip into the excavation or a slope of four horizontal to one vertical (4H:1V) or steeper.
UNCONFINED COMPRESSIVE STRENGTH (SOIL). The load per unit area at which a soil will fail in compression. It can be determined by laboratory testing, or estimated in the field using a pocket penetrometer, by thumb penetration tests, and other methods.
UNDERLAYMENT. One or more layers of approved material over which a roof covering is applied.
UNDERPINNING. The alteration of an existing foundation to transfer loads to a lower bearing stratum using new piers, piles, or other structural support elements installed below the existing foundation.
UNENCLOSED PERIMETER. Any exterior portion of a building that is not solidly enclosed with the permanent façade, including the windows; or any exterior edge of a roof that is not enclosed with its permanent parapet or guardrail.
UNSTABLE (REACTIVE) MATERIAL. A material, other than an explosive, which in the pure state or as commercially produced, will vigorously polymerize, decompose, condense or become self-reactive and undergo other violent chemical changes, including explosion, when exposed to heat, friction or shock, or in the absence of an inhibitor, or in the presence of contaminants, or in contact with incompatible materials. Unstable (reactive) materials shall be classified as follows:
   Class 4. Materials that in themselves are readily capable of detonation or explosive decomposition or explosive reaction at normal temperatures and pressures. This class includes materials that are sensitive to mechanical or localized thermal shock at normal temperatures and pressures.
   Class 3. Materials that in themselves are capable of detonation or of explosive decomposition or explosive reaction but which require a strong initiating source or which must be heated under confinement before initiation. This class includes materials that are sensitive to thermal or mechanical shock at elevated temperatures and pressures.
   Class 2. Materials that in themselves are normally unstable and readily undergo violent chemical change but do not detonate. This class includes materials that can undergo chemical change with rapid release of energy at normal temperatures and pressures, and that can undergo violent chemical change at elevated temperatures and pressures.
   Class 1. Materials that in themselves are normally stable but which can become unstable at elevated temperatures and pressure.
USE (MATERIAL ). Placing a material into action, including solids, liquids and gases.
USE/USING (SCAFFOLD). Any work or activity performed on or from the scaffold. In addition, for a suspended scaffold, the use of the scaffold shall include the operation of the scaffold at the site, provided during such operation any vertical or horizontal relocation of the scaffold does not require a modification to the counterweight, or does not require the placement, relocation, or removal of any anchorage, attachment, outrigger beam, tie-back, or connection to the building or structure.
VALUE (OF ALTERATIONS, TO DETERMINE REQUIRED ACCESSIBILITY). The value of alterations shall be determined by adding the estimated cost of the proposed alteration, including minor alterations but excluding ordinary repairs, computed as of the time of submitting the application for construction document approval, or, where no permit is required, computed at the time of the work, to the actual cost of any and all alterations and minor alterations made in the preceding 12-month period. Where the alteration includes an enlargement, the value of the alteration shall include the cost of the enlargement.
VALUE (OF ALTERATIONS, TO DETERMINE REQUIRED FIRE PROTECTION). The value of alterations shall be determined by adding the estimated cost of the proposed alteration, excluding minor alterations and ordinary repairs computed as of the time of submitting the application for construction document approval, to the actual cost of any and all alterations made in the preceding 12-month period. Where the proposed alteration includes an enlargement, the value of such alteration shall also include the cost of the enlargement.
VALUE (OF EXISTING BUILDING OR SPACE). The value of an existing building shall be determined at the option of the applicant on the basis of one and one-quarter times the current assessed valuation of the building, as adjusted by the current State equalization rate, or on the basis of the current replacement cost of the building. The value of an existing space shall be determined on the basis of the current replacement cost of the space. Satisfactory evidence of current replacement cost shall be submitted to the commissioner. Where the alteration includes an enlargement, the value of the existing building shall be determined without including the value of the enlargement.
VAPOR-PERMEABLE MEMBRANE. A material or covering having a permeance rating of 5 perms (2.9 × 10-10 kg/Pa × s × m 2 ) or greater, when tested in accordance with the desiccant method using Procedure A of ASTM E 96. A vapor-permeable material or covering permits the passage of moisture vapor.
VAPOR RETARDER CLASS. A measure of a material or assembly's ability to limit the amount of moisture that passes through that material or assembly. Vapor retarder class shall be defined using the desiccant method of ASTM E 96 as follows:
   Class I: 0.1 perm or less.
   Class II: 0.1 < perm < 1.0 perm.
   Class III: 1.0 < perm < 10 perm.
VARIANCE. See Section G201.1.2.
VAULT. Any space below the surface of a street that is covered over, except those openings that are used exclusively as places for descending, by means of steps to the cellar or basement of any building.
VEGETATIVE ROOF. A system constructed in-situ consisting of either a roof assembly and additional landscape material components, including growing media, engineered soils, filter fabric, integral drainage systems and roof surface to facilitate the growth of vegetation or a pre-vegetated tray or trays no more than 6 inches (152 mm) high and assembled on top of a roof covering.
VEHICLE BARRIER. A component or a system of components near open sides or walls of garage floors or ramps that acts as a restraint for vehicles.
VEHICULAR GATE. A gate that is intended for use at a vehicular entrance or exit and that is not intended for use by pedestrian traffic.
VENEER. A facing attached to a wall for the purpose of providing ornamentation, protection or insulation, but not counted as adding strength to the wall. Veneers are nonstructural in that they do not carry any load other than their own weight.
VENTILATION. The natural or mechanical process of supplying conditioned or unconditioned air to, or removing such air from, any space.
VINYL SIDING. A shaped material, made principally from rigid polyvinyl chloride (PVC) that is used as an exterior wall covering.
VISIBLE ALARM NOTIFICATION APPLIANCE. A notification appliance that alerts by the sense of sight.
V-ZONE. Velocity Zones V, VO, VE, or V1-30 (See Coastal High Hazard Area).
WALKABLE FLOOR (CONCRETE CONSTRUCTION). A floor where the concrete slab has been poured and the formwork stripped.
WALKABLE FLOOR (PRECAST CONCRETE CONSTRUCTION). A floor where the frame is erected and the precast concrete floor is fixed in place.
WALKABLE FLOOR (STEEL CONSTRUCTION). A floor where the frame is erected and the deck is tack welded or fixed in place.
WALKWAY, PEDESTRIAN. A walkway used exclusively as a pedestrian trafficway.
WALL. A vertical element with a horizontal length-to-thickness ratio greater than three, used to enclose space.
   Cavity wall. A wall built of masonry units or of concrete, or a combination of these materials, arranged to provide an airspace within the wall, and in which the inner and outer parts of the wall are tied together with metal ties.
   Dry-stacked, surface-bonded walls. A wall built of concrete masonry units where the units are stacked dry, without mortar on the bed or head joints, and where both sides of the wall are coated with a surface-bonding mortar.
   Parapet wall. The part of any wall entirely above the roof line.
WALL, LOAD-BEARING. Any wall meeting either of the following classifications: 
   1.   Any metal or wood stud wall that supports more than 100 pounds per linear foot (1459 N/m) of vertical load in addition to its own weight.
   2.   Any masonry or concrete wall that supports more than 200 pounds per linear foot (2919 N/m) of vertical load in addition to its own weight.
WALL, NONLOAD-BEARING. Any wall that is not a load-bearing wall.
WALL SIGN. Any sign attached to or erected against the wall of a building or structure, projecting no more than 15 inches (381 mm) from the face of the wall, with the exposed face of the sign in a plane parallel to the plane of said wall.
WATERPROOFING. Waterproofing is a protective measure applied to building foundation walls and slabs to prevent moistures and liquid water from passing into interior spaces.
WATER-REACTIVE MATERIAL. A material that explodes; violently reacts; produces flammable, toxic or other hazardous gases; or generates enough heat to cause auto-ignition or ignition of combustible materials upon exposure to water or moisture. Water-reactive materials are classified as follows:
   Class 3. Materials that react explosively with water without requiring heat or confinement.
   Class 2. Materials that react violently with water or cause water to boil upon contact; produce flammable, toxic or other hazardous gases upon contact with water; or upon contact with water generate sufficient heat to cause auto-ignition of adjoining combustible materials.
   Class 1. Materials that may react with water with some release of energy, but not violently.
WATER-RESISTIVE BARRIER. A material behind an exterior wall covering that is intended to resist liquid water that has penetrated behind the exterior wall covering from further intruding into the exterior wall assembly.
WEATHER-EXPOSED SURFACES. Surfaces of walls, ceilings, floors, roofs, soffits and similar surfaces exposed to the weather except the following:
   1.   Ceilings and roof soffits enclosed by walls, fascia, bulkheads or beams that extend a minimum of 12 inches (305 mm) below such ceiling or roof soffits.
   2.   Walls or portions of walls beneath an unenclosed roof area, where located a horizontal distance form an open exterior opening equal to at least twice the height of the opening.
   3.   Ceiling and roof soffits located a minimum horizontal distance of 10 feet (3048 mm) from the outer edges of the ceiling or roof soffits.
WET-CHEMICAL EXTINGUISHING SYSTEM. A solution of water and potassium-carbonate-based chemical, potassium-acetate-based chemical or a combination thereof, forming a fire-extinguishing agent.
WHEEL MOUNTED CRANE (MULTIPLE CONTROL STATIONS). A mobile crane consisting of a rotating superstructure, operating machinery, and operator's station and boom, mounted on a crane carrier equipped with axles and rubber-tired wheels for travel, a power source(s), and having separate stations for driving and operating.
WHEEL MOUNTED CRANE (SINGLE CONTROL STATION). A mobile crane consisting of a rotating superstructure, operating machinery, and boom, mounted on a crane carrier equipped with axles and rubber-tired wheels for travel, a power source, and having a single control station for driving and operating.
WHEELCHAIR SPACE. A space for a single wheelchair and its occupant.
WIND SPEED, V (BASIC). Basic design wind speeds.
WIND SPEED, Vasd. (ALLOWABLE STRESS DESIGN). Allowable stress design wind speeds.
WIND-BORNE DEBRIS REGION. Areas within hurricane-prone regions located:
   1.   Within 1 mile (1.61 km) of the coastal mean high water line where the basic design wind speed, V, is 130 mph (58 m/s) or greater.
   For Risk Category IV buildings and structures, and Risk Category III health care facilities, the wind-borne debris region shall be based on the basic design wind speed for Risk Category IV on Table 1609.3.
WINDER. A stair tread with nonparallel edges.
WIRE BACKING. Horizontal strands of tautened wire attached to surfaces of vertical supports that, when covered with the building paper, provide a backing for cement plaster.
WIRELESS PROTECTION SYSTEM. A system or a part of a system that can transmit and receive signals without the aid of wire.
WOOD SHEAR PANEL. A wood floor, roof or wall component sheathed to act as a shear wall or diaphragm.
WOOD STRUCTURAL PANEL. A panel manufactured from veneers, wood strands or wafers or a combination of veneer and wood strands or wafers bonded together with waterproof synthetic resins or other suitable bonding systems. Examples of wood structural panels are:
   Composite panels. A wood structural panel that is comprised of wood veneer and reconstituted wood-based material and bonded together with waterproof adhesive;
   Oriented strand board (OSB). A mat-formed wood structural panel comprised of thin rectangular wood strands arranged in cross-aligned layers with surface layers normally arranged in the long panel direction and bonded with waterproof adhesive; or
   Plywood. A wood structural panel comprised of plies of wood veneer arranged in cross-aligned layers. The plies are bonded with waterproof adhesive that cures on application of heat and pressure.
WOOD/PLASTIC COMPOSITE. A composite material made primarily from wood or cellulose-based materials and plastic.
WORKING DECK (CONCRETE CONSTRUCTION). The level where the floor is being formed.
WORKING DECK (DEMOLITION). The level where the floor is being broken up.
WORKING DECK (PRECAST CONCRETE CONSTRUCTION). The level where the floor is being placed.
WORKING DECK (STEEL CONSTRUCTION). The floor where the metal decking and steel components are being placed before concrete is poured.
WORKSTATION. A defined space within a fabrication area in which a specific function, laboratory procedure or research activity relating to semiconductor manufacture is conducted. A workstation may include equipment using HPM, hazardous materials storage cabinets, flammable liquid storage cabinets or gas cabinets, ventilation equipment, fire protection devices, detection devices, and electrical devices.
WYTHE. Each continuous, vertical section of a wall, one masonry unit in thickness.
YARD. An open space, other than a court, unobstructed from the ground to the sky, except where specifically provided by this code, on the lot on which a building is situated.
ZERO CLEARANCE VESTIBULE. A limited space on the elevator lobby between the exterior of the hoistway door and the security door attached to the elevator hoistway.
ZONE. A defined area within the protected premises. A zone can define an area from which a signal can be received, an area to which a signal can be sent or an area in which a form of control can be executed.
ZONE, NOTIFICATION. An area within a building or facility covered by notification appliances that are activated simultaneously.
(L.L. 2015/078, 9/2/2015 , eff. 12/31/2015; Am. L.L. 2016/157, 12/6/2016, eff. 5/1/2019 ; Am. L.L. 2017/097, 5/30/2017, eff. 6/1/2019; Am. L.L. 2017/196, 10/16/2017, eff. 10/16/2017; Am. L.L. 2018/003, 12/31/2017, eff. 1/1/2019; Am. L.L. 2020/091, 9/27/2020, eff. 3/26/2021; Am. L.L. 2021/126, 11/7/2021, eff. 11/7/2022; Am. L.L. 2023/077, 6/11/2023, eff. 6/11/2023)
Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 2010/047, L.L. 2012/028, L.L. 2016/157, L.L. 2020/091, L.L. 2021/126 and L.L. 2023/077.
(Am. L.L. 2023/077, 6/11/2023, eff. 6/11/2023)
Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 2023/077.