3303.11.2 Stairs during building construction or enlargements.
BC § 3303.11.2
During new building construction or the enlargement of an existing building, stairs shall be provided at all locations where a permanent stair will be required and shall serve all floors. At least one of the provided stairs must be of permanent construction for its full length; in all other locations, the stairs may be of temporary or permanent construction. Exceptions: 1. Where a floor is open to the public, all stairs required for egress from the floor must be of their permanent construction from that floor to the ground level.
2.Stairs are not required where the floor is closed to the public and the floor is less than 4 stories or 40 feet (12 192 mm) below the topmost working deck, whichever is less.
3.During the construction or enlargement of a building whose primary structural system consists of structural steel, where it is not feasible to provide one or more permanent stairs to serve all floors that are at least 4 stories or 40 feet (12 192 mm) below the topmost working deck, whichever is less, all stairs shall be of their permanent construction up to the level of the topmost completed steel floor, and temporary stairs, acceptable to the commissioner, shall be brought up in all locations to serve all remaining floors that are at least 4 stories or 40 feet (12 192 mm) below the topmost working deck, whichever is less. At a minimum, the temporary stairs shall be made of non-combustible material, be equipped with adequate handrails, be provided with landings that are level with the adjoining floor, and have riser height and tread depths that are uniform, within 1/4 inch (6 mm), for each flight of stairs.
