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http://www.leg.state.nv.us/Division/Research/Publications/Bkground/BP95-04.pdf

1975 Legislation
The original provisions within Chapter 202 were established through Assembly Bill 17
(Chapter 326, Statutes of Nevada 1975) which passed during the 1975 Legislative
Session. It restricts smoking of tobacco in public places to protect human health and
safety. Specifically, smoking is prohibited in elevators, libraries, museums, public
buses, rooms in public buildings (while public meetings are in progress), public areas
of state buildings, and public areas of any medical or dental office. The measure
specifies that separate smoking areas may be provided.