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Planning Guidance for the Installation and Use of Technology Devices for Transportation Operations and Maintenance

ENTERPRISE Transportation Pooled Fund Study

VSL Guideline 4 - Work Zones

Purpose: To post varying speed limits for construction zones in order to only slow traffic when necessary, or to maintain consistent travel speeds to promote safety.

1a. The schedule of the construction activities being performed AND the design of the work zone are such that the vehicles are not required to be slowed to the same speed 24 hours per day. For example, if vehicles are slowed to a speed during the day when workers are present, but when work is not occurring the absence of workers and layout of the construction zone (lane width, geometries, structure) would allow higher speeds.

OR

1b. The construction zone already exists and there is a noticeable differential in the speed of vehicles as they progress through the work zone (where travelers would benefit from slowing earlier).

Note: Many locations include additional fines for speeding in work zones, and the design of any variable speed limit system must consider this aspect before determining if variable speed systems are appropriate for work zones.