§ 27-535 Safe areas.
AC § 27-535
Safe areas shall comply with the following: When provided to serve class one or class two exit openings safe areas shall be separated from assembly spaces by noncombustible construction having a two hour fire-resistance rating, and shall serve as transition areas in the line and direction of exit travel. They shall serve for normal entry to the assembly space and may be used as corridors, lobbies, or lounges. No room or space classified in occupancy group A, B1, D-1, or D-2 shall open upon a safe area. Safe areas shall be at a level not more than six feet above or below the level at which egress is made from the assembly space, except that a separate safe area shall not be required for any assembly space having an occupant load of less than one hundred fifty persons and which is served by a safe area of another assembly space, when such safe area is in the direction of egress. Ventilating systems for safe areas shall not be connected to systems serving any other spaces, unless separated from such systems by fire dampers actuated by smoke detectors meeting the construction requirements of subchapter thirteen of this chapter.
(1)COLLECTING SAFE AREAS. Places of assembly having more than one assembly space may have a collecting safe area that receives the occupant load discharged into it by other safe areas. Collecting safe areas shall be located within six feet above or below the assembly space nearest to grade.
(2)OCCUPANT LOAD. The occupant load of a safe area shall be the aggregate occupant load of all exit openings discharging directly into it. The occupant load of a collecting safe area shall be the aggregate occupant load of all exit openings discharging directly into it, plus fifty per cent of the occupant load of other safe areas discharging into it.
(3)DIMENSIONS. Except as provided in subdivision four of this section, the clear unobstructed floor area of each safe area shall be sufficient to accommodate the total occupant load of the safe area on the basis of two square feet per person, not including space occupied by furniture or equipment. The minimum dimension of such unobstructed space shall be eight feet. The width of the unobstructed space shall be measured at right angles to the direction of travel to an exit and shall not be less than required for the occupant load, on the basis of the exit capacity listed in table 8-1. The height of safe areas shall be at least eight feet at all points.
(4)SAFE AREAS NEAR GRADE. When a safe area provides egress to an open exterior space, either directly or through a vestibule, the safe area need not provide the floor area required by subdivision three of this section when the level of discharge from the safe area to the open exterior space is not more than four feet above or below the grade of the open exterior space.
(5)RAMPS AND STEPS. Ramps in safe areas shall have a gradient of not more than one in twelve, except that when not exceeding six feet in length, the gradient may be not greater than one in ten. Steps in safe areas shall comply with the following requirements: a. No riser shall be less than six inches nor more than seven and one-half inches high. b. No riser shall vary in height from the riser immediately above or below it. c. Treads in flights of steps shall be at least ten and one-half inches wide exclusive of nosing, and, except as provided in paragraph d of this subdivision, the sum of two risers plus the width of one tread shall be at least twenty-four inches but not more than twenty-five and one-half inches. d. No change in levels shall have less than three risers, except that where the intervening tread is between twenty-eight inches and thirty-six inches, two risers may be used when the edge of each tread is marked by a contrasting color stripe. e. Where exit openings from an assembly space are above or below the level of the safe area, a platform shall be provided at the same level as that of the exit opening. The platform shall be at least one foot wider on each side than the exit opening, and shall extend a minimum of six feet in the direction of exit travel. The sides of such platforms, and of steps or ramps leading from them, shall be protected by guards at least three feet high.
(6)EXITS FROM SAFE AREAS. The capacity of exits from safe areas shall be as listed in table 8-1. Exit openings from safe areas shall discharge into exit types as provided in subchapter six of this chapter.
(7)DOOR HARDWARE. Doors from safe areas or from exits from safe areas opening directly to the outdoors and furnished with locks shall be equipped with fire exit bolts complying with the requirements of paragraph two of subdivision (k) of section 27-371 of subchapter six of this chapter.
