(a) Unless specifically excluded in subsection (b) of this section, it shall be unlawful for any person to obtain employment in an establishment licensed or permitted to operate under this article, for any form of consideration, or to exhibit or display specified anatomical areas in an establishment licensed or permitted to operate under this article, unless and until such person shall have first obtained an adult entertainment permit or temporary permit from the city manager.

(b) This division shall not apply to employees engaged exclusively in performing janitorial or maintenance services.