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When a floor area has access to areas of refuge that comply with the requirements of section 27-372 of article five of this subchapter, the number of persons for whom vertical exits are to be provided may be reduced to fifty per cent of the occupant load of the floor area when one area of refuge is provided, and may be reduced to thirty-three and one-third per cent of the floor area when two areas of refuge are provided. This section shall not be applicable to any new or altered place of assembly, except for such places of assembly in fully sprinklered office buildings which occupy less than twenty percent of the floor area occupied by the principal use.
Article 5: Access Requirements and Exit Types
(a) Means of egress shall be provided for all buildings by one or more of the facilities listed below. Access and exit facilities not specifically covered in this section shall not be used to satisfy the exit requirements of this code. Fire escapes shall not be permitted on new construction, with the exception of group homes. Fire escapes may be used as exits on buildings existing on December sixth, nineteen hundred sixty-eight when such buildings are altered, subject to the approval of the commissioner, or as provided in subdivision (b) hereof. Elevators or escalators shall be provided in all new buildings exceeding four stories in height except that buildings or building sections classified in occupancy group H-2 exceeding one story in height and buildings or building sections classified in occupancy group G or J-1 exceeding two stories in height shall be provided with elevators.
(b) In group homes all floors used by children shall have alternate exits remotely located from each other and readily accessible to the occupants. Fire escapes shall be permitted as the second means of egress.
Corridors shall be kept readily accessible and unobstructed at all times. Corridors shall be kept free of combustible contents except that in buildings classified in occupancy groups G, H-1 and H-2, combustible contents may be stored in noncombustible lockers and combustible bulletin boards meeting the requirements of table 5-4 shall be permitted.
(a) Capacity. The capacity and minimum width of corridors shall be as listed in table 6-1. Width shall be measured in the clear between the narrowest points produced by any projections such as radiators, lockers, drinking fountains, or room or locker door swings, except that such width may be reduced by projections up to eighteen inches wide to the extent of two inches per unit of exit width if the total area of such projections does not exceed five per cent of the area of the wall on which they occur.
(b) Height. Corridors shall have a clear height of seven feet six inches for at least seventy-five per cent of the floor area, with no point less than seven feet in height. No projection below the ceiling shall be located so as to obstruct full view of exit signs.
(c) Length. Corridors shall be subdivided by smoke barriers, as defined in subchapter two, into the following lengths:
Educational occupancy group G | 300 ft. |
Institutional occupancy groups H-1 and H-2 | 150 ft. |
Residential occupancy groups J-1 and J-2 | 150 ft. |
Where smoke barriers are penetrated by doors, such doors shall be smoke stop doors in conformance with subdivision (c) of section 27-371 of this article. (d) Dead ends. Dead ends in corridors shall not exceed the length listed in table 6-1, except that in all occupancy groups except occupancy group H, when a corridor is completely enclosed in construction having a two hour fire-resistance rating, with all corridor doors being self-closing and having a fire protection rating of one and one-half hours, the permissible length of dead ends may be increased one hundred per cent above the length listed in table 6-1. Dead end distance shall be measured from the centerline of the door opening nearest to the closed end of the corridor to the center of an exit door opening, or the center of that point in the corridor where travel to two or more exits becomes available in two directions.
(f) Exterior corridors. Exterior corridors shall be roofed, and shall have solid floors drained to prevent accumulations of standing water. Such floors may serve as fire canopies when so constructed. Exterior corridors shall be protected along their outer side by guards or parapets at least three feet six inches high. Openings in guards or parapets shall be of such dimensions as to prevent the passage of a five inch dia. ball. Where the outer side of an exterior corridor is more than fifty per cent enclosed with solid material, it shall be treated as an interior corridor.
(g) Balconies. Balconies may serve as a means of egress from dwelling units in buildings classified in occupancy group J-2 under the following conditions:
(1) They shall serve at least two dwelling units.
(2) They shall be constructed as required for exterior corridors, except that parapets or guards shall not be higher than four feet on the outer side of the balcony.
(3) The dwelling units served by balconies shall be separated from each other by construction having at least a two hour fire resistance rating. Such separation shall extend at least three feet beyond the outside face of the exterior wall of the building, although such projection may be reduced to two feet six inches provided that any window opening on each such balcony served by the fire separation shall be at least two inches from such fire separation for every one inch that such separation is less than thirty-six inches. An opening at least twenty inches wide shall be provided between the end of this separation and the balcony parapet or guard, and the opening shall be maintained free and unobstructed for the full height of the balcony, except that privacy screens openable from either side may be permitted in the opening.
(4) Access from dwelling units to the balconies shall be through doors having glass panels at least two feet wide and four feet high, without muntins, screens, or other obstructions to hinder entry by breaking the glass panels. The doors shall be lockable only from the inside by devices that can be easily released from the outside after breaking the glass. A combination lock or lock required to be opened by a key or removable device or tool shall not be used.
(h) Construction.
(1) Interior corridors. Interior corridors shall be completely enclosed within fire separations to provide a minimum fire-resistance rating of one hour except as otherwise provided in subparagraphs a through c of this paragraph:
a. For buildings or spaces classified in occupancy group J-1 or J-2 of combustible construction group II exceeding two stories in height, except for buildings not exceeding three stories in height and occupied exclusively by not more than one family on each story without boarders, roomers or lodgers, corridors shall be enclosed within fire separations providing a minimum fire-resistance rating of two hours.
b. Corridor partitions may be omitted or may be constructed of unrated noncombustible material in buildings in occupancy group H-2 in the following instances: nurses' stations not exceeding three hundred fifty square feet in area, waiting spaces, lounges and recreational spaces for patients and visitors which do not exceed five hundred square feet in area, spaces used solely for public telephones, and all other spaces which are completely protected by an automatic wet sprinkler system complying with the construction requirements of subchapter seventeen of this code.
c. Corridor partitions may be omitted in spaces of occupancy group H-1 used for detention of persons under legal restraint.
(2) Exterior corridors and balconies. Exterior corridors and balconies shall be constructed of noncombustible materials.
(i) Borrowed lights. No operable transoms shall be permitted in walls of corridors. In corridors required to have a one hour fire-resistance rating, fixed one-quarter inch wire glass panels may be installed in not more than twenty percent of the common wall between the corridor and any room or space, provided that no panel exceeds seven hundred twenty square inches in area; however, openings permitted in paragraph three of subdivision (h) of section 27-370 of this article may be permitted provided all of the limitations and requirements specified in that section are complied with, except that openings in corridor walls serving as fire divisions required to have a fire-resistance rating shall be limited to those specified in section 27-342 of article five of subchapter five of this chapter.
(j) Ventilation. Corridors shall be ventilated in accordance with the requirements of subchapter twelve of this chapter. Corridors shall not be used as open plenums or as ducts to exhaust air from rooms or spaces opening upon them, except as permitted in reference standard RS 13-1.
(k) Interior finish. The interior finish of corridors shall be in accordance with the requirements of table 5-4.
Exit passageways shall be maintained free of obstructions at all times. Not more than fifty percent of the total number of vertical exits provided for a building may be served by a single exit passageway, except as provided in subdivision (h) of section 27-370 of this article.
(a) Capacity. The capacity of exit passageways shall be as listed in table 6-1.
(b) Width. The width of an exit passageway serving one vertical exit shall be equal to the width of the vertical exit. The width of an exit passageway serving two or more vertical exits shall be equal to seventy-five percent of the width of all of the vertical exits that it serves. Width shall be measured in the clear between the narrowest points at any projections such as radiators, door swings, or pilasters.
(c) Height. Exit passageways shall have a clear height of seven feet six inches for at least seventy-five per cent of the floor area, with no point less than seven feet in height. No projection below the ceiling shall be located so as to obstruct full view of exit signs.
(e) Construction. The construction of exit passageways shall be as required by table 3-4 for the applicable construction class of the building.
(f) Openings. No openings other than exit doors shall be permitted in exit passageways, except as provided in subdivision (h) of this section.
(g) Interior finish. The interior finish of exit passageways shall be in accordance with the requirements of table 5-4.
(h) Street floor lobbies. Street floor lobbies may be used as exit passageways when they comply with the requirements of subdivisions (a) through (g) of this section subject to the following modifications:
(1) VERTICAL EXITS SERVED. One hundred per cent of the total number of vertical exits provided for a building may be served by a street floor lobby, if egress is provided in two different directions from the discharge points of all vertical exits to open exterior spaces that are remote from each other.
(2) WIDTH. Street floor lobbies serving as exit passageways shall be increased in width to accommodate the occupant load of all communicating spaces on the lobby floor that exit through them. The capacity per unit of width shall be as listed in table 6-1.
(3) OPENINGS. Openings between street floor lobbies serving as exit passageways and elevators or communicating spaces shall comply with the following:
a. Doors.
1. Doors to stairways and elevators, and unsprinklered communicating spaces classified in occupancy group B-2, D-2, F-1 or F-2 shall be self-closing fire doors having a one and one-half hour fire protection rating.
2. Doors to unsprinklered communicating spaces classified in occupancy group G, H or J, or sprinklered communicating spaces classified in occupancy group B-2, D-2, F-1 or F-2 may be either:
(a) self-closing fire doors having a three-quarter hour fire protection rating, or
(b) glass or other noncombustible doors installed in conjunction with automatic fire doors having a one and one-half hour fire protection rating, with sprinkler heads installed over the doors on the room side.
3. No other door openings shall be authorized except as otherwise provided in this section.
b. Other openings. Other openings to spaces classified in occupancy group C, E, F, G, H or J shall be permitted, provided they have a maximum length of eight feet and a maximum height of eight feet, are glazed by one-quarter inch polished plate glass or equivalent and are protected by automatic fire doors having a one and one-half hour fire protection rating and by automatic sprinklers complying with the construction requirements of subchapter seventeen of this chapter over the openings on the room side.
c. Separations and limitations. Openings permitted by subparagraphs a and b of this paragraph shall not exceed in total length fifty per cent of the length of such enclosure wall except where the length of such wall is less than sixteen feet. Adjoining openings shall be separated from each other a minimum of three feet by construction having a two hour fire-resistance rating.
d. Notwithstanding the restrictions in subparagraphs a, b, and c of this paragraph, the following openings may be authorized:
1. A space classified in occupancy group C, E, F-3 or, F-4 within fire separations having a minimum fire-resistance rating of one hour, with an area not exceeding twenty-five hundred square feet, may have an unlimited length of show window under the following conditions:
(a) The maximum depth of show window shall be three feet.
(b) Automatic sprinklers complying with the construction requirements of subchapter seventeen of this chapter, shall be provided in the show window display area.
(c) The show window display area shall be protected on all sides, except for the glazed window, by construction having a two hour fire-resistance rating with access provided by means of a fireproof self-closing door having a three-quarter hour fire protection rating.
(d) The show window shall be glazed by one-quarter inch polished plate glass or equivalent.
(e) Glass or other noncombustible doors may be used for entrance to or egress from the space within fire separations when installed in combination with automatic fire doors having a one and one-half hour fire protection rating. Such automatic fire doors shall be located on the room side and shall be held open by approved door-holding devices actuated to release automatically upon the activation of smoke detecting devices, whether of the photoelectric cell or other approved type. In addition, automatic sprinkler heads, complying with the construction requirements of subchapter seventeen of this chapter, shall be provided over the door openings on the room side.
2. A space classified in occupancy group C, E, F-3, or F-4 within fire separations having a minimum fire-resistance rating of one hour, with an area not exceeding three thousand square feet, may have a maximum total length of unprotected openings upon a corridor or exit passageway not exceeding fifty percent of the space frontage along such corridor or exit passageway under the following conditions:
(a) The entire space shall be provided with automatic sprinklers complying with the construction requirements of subchapter seventeen of this chapter.
(b) The show window shall be glazed by one-quarter inch polished plate glass or equivalent.
(c) All corridor or exit passageway doors shall be self-closing, noncombustible, and smokeproof.
3. Show windows or other openings of unlimited lengths and heights shall be permitted on any corridor or exit passageway without requirements for fire-resistance doors under the following conditions:
(a) The entire floor area, including the corridors or exit passageways, shall be provided with automatic sprinklers complying with the construction requirements of subchapter seventeen of this chapter.
(b) The occupancy of all spaces on the floor shall be limited to occupancy groups C, E, F-3 and F-4.
(c) The widths of the corridors or passageways shall exceed the requirements of table 6-1 or subdivision (b) of this section, whichever is applicable, by at least fifty percent.
(d) All doors opening on the corridors or exit passageways shall be smokeproof, noncombustible self-closing doors.
(e) Show windows or other openings shall be glazed by one-quarter inch polished plate glass or equivalent.
(f) Each corridor or exit passageway shall be provided with a fresh air intake, a positive smoke exhaust system and smoke detectors which, when activated, shall permit circulation only of fresh air.
(4) OCCUPANCY. Street floor lobbies serving as exit passageways may be occupied by newsstands, candy and tobacco stands, information booths or similar occupancies, if such stands or booths are constructed of noncombustible materials, or of materials which comply with the requirements of section 27-348 of article five of subchapter five of this chapter for interior finish for exit passageways, provided that such stands or booths:
a. do not occupy more than one hundred square feet or five percent of the net floor area of the lobby, whichever is greater; and
b. do not reduce the required clear width of the lobby at any point; and
c. if constructed of combustible materials are protected by no less than two automatic sprinkler heads. Water for such sprinkler heads may be supplied from the domestic water supply system.
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