(A) It shall be the duty of the officers of the Police Department to enforce all street traffic laws and all of the state vehicle laws applicable to street traffic.
(B) Officers of the Police Department are hereby authorized to direct all traffic by voice, hand or signal in conformance with traffic laws; provided that, in the event of a fire or other emergency or to expedite traffic or to safeguard pedestrians, officers of the Police Department may direct traffic as conditions may require notwithstanding the provisions of the traffic laws.
(C) Officers of the Fire Department, when at the scene of a fire, may direct or assist the police in directing traffic thereat or in the immediate vicinity.