1023.5 Penetrations.

Penetrations into or through interior exit stairways and ramps are prohibited except for equipment and ductwork necessary for independent ventilation or pressurization, hydronic piping and related heating equipment limited to serving the interior exit stairway or ramp in which such piping and equipment is located, sprinkler piping, standpipes, electrical raceway for Fire Department communication systems and electrical raceway serving the interior exit stairway and ramp and terminating at a steel box not exceeding 16 square inches (0.010 m 2 ). Such penetrations shall be protected in accordance with Section 714. There shall not be penetrations or communication openings, whether protected or not, between adjacent interior exit stairways and ramps.

   Exception: Membrane penetrations shall be permitted on the outside of the interior exit stairway and ramp. Such penetrations shall be protected in accordance with Section 714.3.2.

1023.6 Ventilation.

Equipment and ductwork for interior exit stairway and ramp ventilation as permitted by Section 1023.5 shall comply with one of the following items:

   1.   Such equipment and ductwork shall be located exterior to the building and shall be directly connected to the interior exit stairway and ramp by ductwork enclosed in construction as required for shafts.

   2.   Where such equipment and ductwork is located within the interior exit stairway and ramp, the intake air shall be taken directly from the outdoors and the exhaust air shall be discharged directly to the outdoors, or such air shall be conveyed through ducts enclosed in construction as required for shafts.

   3.   Where located within the building, such equipment and ductwork shall be separated from the remainder of the building, including other mechanical equipment, with construction as required for shafts.

In each case, openings into the fire-resistance-rated construction shall be limited to those needed for maintenance and operation and shall be protected by opening protectives in accordance with Section 716 for shaft enclosures.

The interior exit stairway and ramp ventilation systems shall be independent of other building ventilation systems.

(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.

1023.7 Interior exit stairway and ramp exterior walls.

Exterior walls of the interior exit stairway or ramp shall comply with the requirements of Section 705 for exterior walls. Where nonrated walls or unprotected openings enclose the exterior of the stairway or ramps and the walls or openings are exposed by other parts of the building at an angle of less than 180 degrees (3.14 rad), the building exterior walls within 10 feet (3048 mm) horizontally of a nonrated wall or unprotected opening shall have a fire-resistance rating of not less than 1 hour. Openings within such exterior walls shall be protected by opening protectives having a fire protection rating of not less than 3/4 hour. This construction shall extend vertically from the ground to a point 10 feet (3048 mm) above the topmost landing of the stairway or ramp, or to the roof line, whichever is lower.

1023.8 Discharge identification.

An interior exit stairway and ramp shall not continue below its level of exit discharge unless an approved barrier is provided at the level of exit discharge to prevent persons from unintentionally continuing into levels below. Directional exit signs shall be provided as specified in Section 1013. An approved barrier shall consist of partitions, doors, or gates separating the portion of the interior exit stairway above grade from the portion below grade. Where doors or gates are provided as approved barriers, such doors or gates shall be self-closing, opening in the direction of exit travel from the floors below grade, and provided with landings in accordance with Sections 1010.1.5 and 1010.1.6.

   Exceptions:

      1.   Such barrier separating the above-grade portion of the interior exit stairways and ramps from the portion below grade shall not be required in Group E and R-3 occupancies.

      2.   Such barrier separating the above-grade portion of the interior exit stairways and ramps from the portion below grade shall not be required where the stairway or ramp design is intended to continue the path of egress through a below grade level.

1023.9 Stairway identification and floor level signs.

Signs identifying stairways shall comply with Section 1023.9.1. Signs identifying floor levels shall comply with Sections 1023.9.2 through 1023.9.5.

1023.9.1 Stairway identification signs.

A stairway identification sign indicating each stair by alphabetic letter shall be posted on both sides of each stair door. The alphabetic letters designating the identification of the interior exit stairway and ramp shall be not less than 3 inches (76.2 mm) in height. Such sign shall comply with Items 2, 5 and 6 of Section 1023.9.4.

1023.9.2 Floor identification signs.

A floor identification sign shall be provided at each floor landing in an interior exit stairway and ramp connecting more than three stories. Such sign shall designate:

   1.   The floor level;

   2.   The terminus of the top and bottom of the interior exit stairway and ramp;

   3.   The identification of the interior exit stairway and ramp;

   4.   The story of the exit discharge; and

   5.   The availability of roof access from the interior exit stairway and ramp for the Fire Department.