Rides, elevators, hoists or any mechanical device provided for and accessible to the public shall not begin operation until authorized by the building inspector and shall stop operation at any time the building inspector gives notice in writing that he wishes to inspect or test the same or he considers that the same may not be safe for use. The method of making tests and the determination of safety shall be left to the discretion of the building inspector. All tests shall be reasonable. (Code 1941, Art. 96-5)