Section 477.120 - Exits, open stairways and vertical shafts1. Except as otherwise provided in subsection 2, the owner or operator of any building, except a single-family detached dwelling, shall:(a) Equip every exit corridor and other means of exit with emergency lighting of a type approved by the authority which permits the safe evacuation of the building.(b) Except as otherwise provided by the authority, equip every door to an exit corridor which serves 30 or more occupants with a device, approved by the authority, which closes the door.(c) Except as otherwise provided by the authority, immediately provide adequate facilities for exit.(d) If the building has three stories or more, enclose every open stairway or vertical shaft with: (1) Construction whose resistance to fire has been approved by the authority; or(2) Alternate means approved by the authority which afford equivalent protection to life and property from fire.2. A medical facility or facility for the dependent is exempt from the provisions of paragraph (b) of subsection 1 with regard to the door to a patient's room if smoking in the patient's room is prohibited or permitted only when: (a) An employee of the facility is present; or(b) Smoking material is wholly contained within a device designed for such use and approved by the State Fire Marshal.3. Upon a showing of practical difficulty or unnecessary hardship, the authority may grant an exemption from the provisions of paragraph (c) of subsection 1 if it is clearly evident that the safe evacuation of the building will not be hindered thereby.4. When an exemption is granted pursuant to subsection 3, the authority shall record the details of and reasons for the exemption.Added to NRS by 1981, 1569; A 1983, 809; 1985, 918, 1763Added to NRS by 1981, 1569; A 1983, 809; 1985, 918, 1763