§ 27-532 Aisles and cross aisles.
AC § 27-532
Assembly spaces shall be served by aisles, cross aisles, or other unobstructed floor areas providing access to exits, except as permitted for bleacher seating in paragraph two of subdivision (a) of section 27-531 of this article.
(a)The capacity of aisles and cross aisles shall be adequate to serve all persons for whom they provide a primary path of travel to an exit. (See section 27-533 of this article.) (1) CAPACITY. The capacity of aisles and cross aisles shall be as listed in table 8-1. The unit of exit width shall be twenty-two inches. Seats or other facilities shall not project into an aisle or cross aisle so as to reduce the width of the aisle or cross aisle more than one inch per unit of exit width.
(2)MINIMUM WIDTH. Aisles and cross aisles shall have a minimum width of forty-four inches except that the width may be at least thirty-six inches under any one or more of the following conditions: a. In any assembly space having a total of not more than three hundred occupants. b. When not more than the number of persons permitted for one unit of exit width is served. c. At the narrowest point when a tapered aisle is permitted under paragraph three of this subdivision. d. When an aisle parallels and is alongside an enclosure wall or partition that is provided with exit doors spaced not more than sixteen feet on centers, provided such aisle serves only the rows of seats adjacent to it.
(3)TAPERED AISLES. Tapered aisles shall be used where egress is provided only at one end of the aisle, except that uniform aisles may be used when their width for the entire length will accommodate eighty per cent of the total occupant load served by the aisle. Tapered aisles shall be widened gradually so that their width at the point of discharge provides for the entire occupant load of the aisle.
(4)UNIFORM AISLES. Aisles of uniform width shall be used where egress is provided at both ends of an aisle by either cross aisles or exit doors. The width of uniform aisles shall not be less than required for sixty per cent of the total occupant load served by the aisles.
(5)AISLE WIDTH AT OPENINGS. When an aisle or cross aisle discharges directly into exit openings, a space shall be provided in front of such openings that is at least as wide as such openings and at least as deep as the width of the aisle or cross aisle.
(6)CROSS AISLES. Cross aisles, at any point shall not be closer than twelve feet to a stage area using scenery or scenic elements. Steppings shall not be permitted in cross aisles.
(7)AISLE GRADIENTS AND STEPPINGS. The floors of aisles shall have a gradient of not more than one in eight. Where differences in levels require a greater gradient, steps shall be used, complying with the following: a. When one riser only is used between levels of platforms, its height shall not exceed eight inches, and where more than one riser is used, none shall exceed seven and three-quarter inches. b. No riser shall be less than four inches high. c. No riser shall vary from the height of the riser immediately above or below except that risers that are separated by a tread of seventeen inches or more may vary up to one-quarter inch. d. The width of treads of intermediate steps between platform levels shall be at least nine and one-half inches, but not more than ten and one-half inches, exclusive of nosings. e. Treads at the level of platforms and seventeen inches or more in width may slope not more than one-quarter inch in twelve inches. f. No steps shall be used to enter a row of seats from an aisle unless an unobstructed floor space of at least seven square feet is provided at the level of the aisle, between the aisle and the steps. g. Each step in an aisle shall be marked along its nosing with a permanent contrasting color stripe, and shall be provided with a step light. h. The line of risers of aisle steppings shall deviate no more than twenty degrees from a line perpendicular to the centerline of the aisle.
(8)STEPPED AISLE LANDINGS. Stepped aisles shall be provided with landings at exit openings, and shall have a length equal to at least the width of the aisle and a slope of not more than one in twelve.
(9)LIGHTING. Aisles and cross aisles shall be provided at all times with at least one-half foot candle of artificial illumination by electrical means.
(10)VOMITORIES. Vomitories within assembly spaces shall comply with all of the requirements for aisles, and shall have a clear ceiling height of at least seven feet.
