Whenever the plumbing inspector shall find plumbing work being done in violation of the city ordinances, he shall have the power to order the work stopped until the ordinances are complied with. It is unlawful to continue any such work after a stop order has been issued, except upon written order of the mayor or of the plumbing inspector; provided that when such a stop order is an oral order, it shall be followed by a written stop order within an hour. (Prior code § 2-10-3)