"Commercial system" means an individual sewage disposal system that serves one or more buildings which are not used as single-family dwellings. The term includes, without limitation, an individual sewage disposal system serving offices, watchmen's quarters, bunkhouses, labor camps, parking facilities for recreational vehicles, factories, multiple-dwelling structures, hotels and shopping centers.
Nev. Admin. Code § 444.755
NRS 439.200, 444.650