Cal. Health & Safety Code § 13115

(a) It is unlawful for any person, firm, or corporation to establish, maintain, or operate any circus, side show, carnival, tent show, theater, skating rink, dance hall, or a similar exhibition, production, engagement, or offering or other place of assemblage in or under which 15 or more persons may gather for any lawful purpose, in any tent, awning, or other fabric enclosure unless a tent, awning, or other fabric enclosure, and all auxiliary tents, curtains, drops, awnings, and all decorative materials, are made from a nonflammable material or are treated and maintained in a flame-retardant condition. This subdivision shall not apply to tents designed or manufactured for children’s play, camping, backpacking, or mountaineering, or those used to conduct committal services on the grounds of a cemetery, nor shall this subdivision apply to tents, awnings, or other fabric enclosures erected and used within a sound stage, or other similar structural enclosure that is equipped with an overhead automatic sprinkler system.

(b) It shall be unlawful for any person to manufacture, sell, or offer for sale any tent designed and intended for use for occupancy by less than 15 persons unless the tent is made from flame-retardant fabrics or materials approved by the State Fire Marshal. A tent described in this subdivision shall be labeled in a manner specified by the State Fire Marshal. Any manufacturer of tents for sale in this state who fails to use flame-retardant fabrics or materials or who fails to label them as specified by the State Fire Marshal shall be strictly liable for any damage that occurs to any person as a result of a violation of this section.

(c) (1) “Flame retardant,” as used in this section, means a fabric or material resistant to flame or fire to the extent that it will successfully withstand standard fire-resistive tests adopted and promulgated by the State Fire Marshal.