Did you know that 30% of fatal work zone crashes are caused by speeding? Also, workers being fatally struck by vehicles while working on foot account for 45% of fatalities recorded at U.S. construction sites. Speed management devices are designed to help lower speeds, and have been shown to lower them by 5 to 7 MPH.
As part of a connected work zone, speed management devices can be programmed to display a lower speed limit when workers are detected on the site or when the work site status is “active”. These devices can also communicate the real-time speed limit to navigation systems such as Waze, allowing drivers be aware of the lower speed limit before reaching the work site.
Work zone speed management devices typically consist of one or more of the following:
These signs should be spaced every mile or moved to be ¼ to ½ mile upstream of areas of concern. This is the usual spacing for areas with multiple work crews or where the work activity area relocates often.
To help improve work zone safety, Ver-Mac worked closely with the Ohio DOT to develop a work zone digital speed limit (WZDSL) trailer with beacons that flash when workers are present on the site and the speed limit has been temporarily lowered.
WZDSL signs convey the speed limits for current conditions and can be placed anywhere within the work zone limits.
Speed awareness signs are ideal for areas where you need to remind motorists of the work zone speed limit, and how fast they are traveling relative to that limit. The goal is speed awareness and harmonization of vehicles passing the area of concern.
Winner of an ATSSA Innovation Award, the Speed Wizard combines a work zone digital speed limit (WZDLS) and speed awareness system on the same platform.
The combination of a WZDSL and speed awareness sign on a single trailer provides ultimate flexibility. By having fewer devices in the field, more space is available for vehicles and work activities.
Our digital speed limit and other speed management signs are intended to increase awareness in critical locations, such as when road workers are near traffic without positive protection or when the work zone presents difficult geometrics (narrow lanes, short sight distance, lane shifts, etc.).
As with all effective speed limit policies, speed limits must always be appropriate for each application. Lowering speeds in work zones to improve safety does not guarantee motorist compliance. It does, however, raise awareness and encourage compliance.
Beyond what they do on the ground, speed management devices extend their features and their reach when they are part of a connected work zone.
Digital speed limit signs will display the appropriate speed limit when work zones are active, and will revert to the higher, regular speed limit when conditions permit.
A site is considered active:
For additional awareness, the work zone digital speed limit trailer will activate its flashing beacons, and the Speed Wizard will display speed feedback information to help protect workers.
In connected work zones, traffic data from speed feedback devices can be pushed through Waze and the Work Zone Data Exchange to reach motorists, Departments of Transportation (DOTs), Traffic Management Centers (TMCs), navigation systems, connected vehicles, and more.
Speed Limit Management Systems are mainly used in the following situations: