Option:
The Advisory Speed (W13-1) plaque may be used to indicate the recommended speed for a condition.
Standard:
The Advisory Speed plaque shall carry the message XX km/h (XX M.P.H). The speed shown shall be a multiple of 10 km/h (5 mph).
Except in emergencies or when the condition is temporary, an Advisory Speed plaque shall not be installed until the recommended speed has been determined by an engineering study.
Guidance:
Because changes in conditions, such as roadway geometrics, surface characteristics, or sight distance, might affect the recommended speed, each location should be periodically evaluated and the Advisory Speed plaque changed if necessary.