California Code, Health and Safety Code - HSC § 13109

The State Fire Marshal, his or her deputies, or his or her salaried assistants, the chief of any city or county fire department or fire protection district and their authorized representatives may enter any building or premises not used for dwelling purposes at any reasonable hour for the purpose of enforcing this chapter. The owner, lessee, manager or operator of any such building or premises shall permit the State Fire Marshal, his or her deputies, his or her salaried assistants and the chief of any city or county fire department or fire protection district and their authorized representatives to enter and inspect them at the time and for the purpose stated in this section.