No such gathering or entertainment shall be held or presented in any premises except 1) private residences, and 2) buildings described in the preceding Section, unless such premises have been inspected by the Fire Marshal or Building Director not more than twelve (12) months before the date of such gathering and found to be free from any fire or other hazard. No structure enclosed by a roof shall be used for such purpose unless the same is constructed of nonflammable materials. Provided, that tents or structures covered by canvas or similar materials may be so used if such canvas or other material has been properly treated so as to be rendered fire resistive. (1968 Code, §22.1002; amd. 1984 Code)