Stairways, Vertical Openings and Doorways

Section 350 Section 350.3920  Stairways, Vertical Openings and Doorways a)         Interior stairways must be enclosed with a minimum of one and three-eighths inch solid core wood door, with a self-closing device at the top and bottom of the stairway.  (B) b)         There shall be no variation exceeding one-fourth inch in the depth of treads or in height of risers in any flight. c)         Usable space under stairs shall not be used for storage.  (B) d)         Means of egress such as stairs, stair landings, balconies, ramps and aisles, located along the edge of open-sided floors and mezzanines, shall have guards to prevent falls over the open side.  Each stair shall have handrails on at least one side. (B) e)         Any light or ventilation shaft, chute and other vertical opening between stories shall be enclosed with construction having a one hour fire resistance rating.  (B) f)         All required exit doors shall be free from any obstruction, chain locking, or holding device.  (B)