Devices to Implement Short-Term Speed Limits in Texas Work Zones

In Texas, speed limits for short-term (less than 12 consecutive h) work zones are used when workers or equipment are not behind a concrete barrier, work activity is within 15 ft of the pavement edge, or work is actually occurring on the pavement. In these situations, speed limit signs for short-term work zones should be posted and visible to the motorists only when work activity is present and covered or removed when no work activity is present. Covering or removing signs can be a tedious task to complete daily or weekly. In addition, this task may interfere with normal traffic flow and expose workers to traffic hazards. Some contractors choose not to cover or remove signs; others simply forget: thus speed limits for short-term regulatory work zones extend into time periods with no apparent need for a speed limit reduction. New sign technologies may simplify the implementation process for speed limits in short-term work zones and could enhance the use of such speed limits in general. However, such technologies have not been used extensively for speed limits in work zones in Texas. Thus, researchers at the Texas Transportation Institute conducted field studies to determine the operational effectiveness of electronic speed limit signs and flexible roll-up speed limit for work zones signs. The researchers recommended the use of both types of signs.