Dynamic Speed Sign

A dynamic speed sign is a traffic calming device designed to slow down drivers by alerting their travel speed as they approach the area. These signs alert the drivers that exceed the posted speed by flashing their speed, encouraging the drivers to reduce their speed. Dynamic speed signs may be installed on either a permanent or a rotating basis.

Application/Considerations/Outcomes

• Appropriate for all roadway classifications
• Apply along mid-block locations; avoid locations where the sign may distract driver’s attention from pedestrian crossings or intersections
• May be applied to school zone areas or construction zones
• May be applied in addition to, or in place of, other traffic calming measures
• May be applied in locations where criteria for physical traffic calming interventions are not met
• Average speed may be reduced by 6 km/h in areas with a dynamic speed sign. In one United Kingdom study, crashes decreased from 3.2 personal injury crashes per year to 1.5 at one site and from 0.7 to 0 in another site (Source: Winnett, M. A. and A. H. Wheeler. Vehicle Activated Signs—A Large Scale Evaluation. Road Safety Division, Department for Transport, 2002)

Image sources: Google Maps, Toronto, City of Hamilton