Gradients or inclined planes shall be employed instead of steps where possible to overcome slight difference of level in or between aisles, corridors and passages. To overcome any difference of level in and between courts, corridors, lobbies, passages and aisles on the ground floor, gradients shall be employed of not over 1 foot in 12 feet, with no perpendicular rises.
Distinct and separate places of exit and entrance shall be provided for each gallery above the first. A common place of exit and entrance may serve for the main floor of the auditorium and the first gallery, provided its capacity be equal to the aggregate capacity of the outlets from the main floor and the said gallery. No passage leading to any stairway communicating with any entrance or exit shall be less than 4 feet in width in any part thereof. From the auditorium opening into the said open courts or on the side street, there shall be not less than 2 exits on each side in each tier from and including the parquet and each and every gallery.
Where the seating capacity is for more than 1,000 people, there shall be at least 2 independent staircases, with direct exterior outlets, provided for each gallery in the auditorium, where there are not more than 2 galleries, and the same shall be lo-cated on opposite sides of said galleries. Where there are more than 2 galleries, 1 or more additional staircases shall be provided, the outlets from which shall communicate directly with the principal exit or other exterior outlets. All such staircases shall be of width proportionate to the seating capacity as elsewhere herein prescribed. Where the seating capacity is for 1,000 people, or less, 2 direct lines of staircase only shall be required, located on opposite sides of the galleries, and in both cases shall extend from the sidewalk level to the upper gallery, with outlets from each gallery to each of said staircases. All inside stairways leading to the upper galleries of the auditorium shall be inclosed on both sides with walls of fireproof materials. Stairs leading to the first or lower gallery may be left open on one side in which case they shall be constructed as herein provided for similar stairs leading from the entrance hall to the main floor of the auditorium. But in no case shall stairs leading to any gallery be left open on both sides. No door shall be open immediately upon a flight of stairs, but a landing at least the width of the door shall be provided between such stairs and such door.
At least 2 independent staircases, with direct exterior outlets, shall also be provided for the service of the stage and shall be located on the opposite sides of the same.
All staircases for the use of the audience shall be inclosed with walls of brick, or of fireproof materials approved by the superintendent of buildings, in the stories through which they pass, and the openings to said staircases from each tier shall be of the full width of said staircase. All stairs within the building shall be constructed of fireproof material throughout. Stairs from balconies and galleries shall not communicate with the basement or cellar. All stairs shall have treads of uniform width and risers of uniform height throughout. Stairs from balconies and galleries shall not communicate with the basement or cellar. All stairs shall have treads of uniform width and risers of uniform height throughout in each flight. Stairways serving for the exit of 50 people shall be at least 4 feet wide between railings or between walls, and for every additional 50 people to be accommodated 6 inches must be added to their width. The width of all stairs shall be measured in the clear between hand rails. In no case shall the risers of any stairs exceed 7 1/2 inches in height, nor shall the treads, exclusive of nosings, be less than 10 1/2 inches wide in straight stairs. No circular or winding stairs for the use of the public shall be permitted. When straight return directly on themselves, a landing of the full width of both flights, without any steps, shall be provided. The outer line of landings shall be curved to a radius of not less than 2 feet to avoid square angles. Stairs turning at an angle shall have a proper landing without winders introduced at said turn. In stairs, when 2 side flights connect with one main flight, no winders shall be introduced, and the width of the main flight shall be at least equal to the aggregate width of the side flights. All stairs shall have proper landings introduced at convenient distances.
All inclosed staircases shall have, on both sides, strong hand rails firmly secured to the wall about 3 inches distant therefrom and about 3 feet above the stairs, but said hand rails shall not run on level platforms and landings where the same is more in length than the width of the stairs. All staircases 8 feet and over in width shall be provided with a centre hand rail of metal, not less than 2 inches in diameter placed at a height of about 3 feet above the center of the treads, and supported on wrought metal or brass standards of sufficient strength, placed not nearer than 4 feet nor more than 6 feet apart, and securely bolted to the treads or risers of stairs, or both, and at the head of each flight of stairs, on each landing, the post or standard shall be at least 6 feet in height, to which the rail shall be secured.
There shall be balconies not less than 6 feet in width in the said open court or courts at each level or tier above the parquet, on each side of the auditorium, of sufficient length to embrace the 2 exits, and from said balconies there shall be staircases extending to the ground level, with a rise of not over 8 1/2 inches to a step and not less than 9 inches tread, exclusive of the nosing. The staircase from the upper balcony to the next below shall be not less than 48 inches in width clear, and from the first balcony to the ground 4 feet in width in the clear where the seating capacity of the auditorium is for 1,000 people or less, 4 feet 6 inches in the clear where above 1,000 and not more than 1,800 people, and 5 feet in the clear where above 1,800 people and not more than 2,500 people, and not over 5 feet 6 inches in the clear where above 2,500 people. All the before-mentioned balconies and staircases shall be constructed of iron throughout, including the floors, and of ample strength to sustain the load to be carried by them, and they shall be covered with a metal hood or awning, to be constructed in such manner as shall be approved by the superintendent of buildings. Where one side of the building borders on the street, there shall be balconies and staircases of like capacity and kind, as before mentioned, carried to the ground.