(1)  A plumbing permit expires on the first of the following:

(a) if the permit specifies a period within which the permit plumbing work is to be commenced and no work has commenced within that period, on the expiry of that period;

(b) if no permit plumbing work has been commenced under the permit and the permit does not specify a period within which the work is to be commenced, on the first anniversary of the permit application being granted under section 169 ;

(c) if the permit does not specify a period for which it is in effect and the period for which it is in effect is not extended under section 173 , on the second anniversary of the permit application being granted under section 169 ;

(d) if the permit specifies a period for which it is in effect and the period for which it is in effect is not extended under section 173 , on the expiry of the period specified in the permit;

(e) if the period for which the permit is in effect is extended under section 173 , on the expiry of the period so extended;

(f) on the issuing of a certificate of completion (permit plumbing work) in respect of the permit plumbing work to be performed under the permit.

(2)  A plumbing permit is only valid while the permit is in effect.