The Chief of Police, by and with the approval of the City Traffic Engineer, is empowered to make regulations necessary to make effective the provisions of the traffic regulations of this City, and to make and enforce temporary or experimental regulations to cover emergencies or special conditions. No such temporary or experimental regulation shall remain in effect for more than ninety days.
The City Traffic Engineer may test traffic control devices under actual conditions of traffic. (3210.9 -- Ord. 996 § 2 (part), 1959).