This section is from the book "The Building Code Of The City Of Boston", by City of Boston Building Department. Also available from Amazon: Building Code of the City of Boston.
Par. 1. - There shall be not less than two exit doors each not less than three feet in width, located on opposite sides of the stage, and opening directly upon a street, alley, court, or courtway leading to a public thoroughfare.
Par. 1. - All rooms in theatres for the use of persons employed therein shall have passages to at least two independent means of exit.
Par. 1. - All doors of exit or entrance shall open outward, and shall be hung so as to swing in such a manner as not to become an obstruction in a passage or corridor, and no such doors shall be fastened so as to be inoperative when the building is occupied by an audience.
Par. 1. - No mirrors shall be so placed as to give the appearance of a doorway or exit, hallway, or corridor, nor shall there be any false doors or windows.
Par. 1. - A common exit may serve for the main floor of the auditorium and the first gallery, provided that its capacity be equal to the aggregate capacity of the outlets from the main floor and the said gallery; and provided that the lowermost run of any exit leading from a gallery shall not open directly at right angles with the central axis of a common exit unless there is a clear space or landing of at least one and one quarter times the width of the exit between the foot of such exit and such centre line or nearest exit doorway.
 
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