In Texas, short term work zone speed limits are reduced speed limits thatare posted only when work activity is present. When the work activity isnot present, the short term work zone speed limit sign is to be removed or covered; thereby allowing the legal speed limit for that segment to revert back to the normal non-work zone speed limit. The major challenges withshort term work zone speed limits is the daily install/remove or uncover/cover process. In this study, researchers conducted a laptop-based laboratory survey to determine: (1) motorist understanding and opinions of alternative short term work zone speed limit signs and their enforceability; (2) if the orange or white light-emitting diode (LED) color used on electronic speed limit (ESL) signs and portable changeable message signs (PCMSs) indicate to motorists that they are advisory or regulatory signs; and (3) motorists preference for short term speed limit displays. The four categories of signs included in the survey were: (1) static work zone signs; (2) ESL signs; (3) "YOUR SPEED signs; and(4) speed limits displayed on PCMSs. Based on the results obtained from this survey, researchers recommend the use of ESL signs and flexible roll-up static work zone speed limit signs for displaying short term work zone speed limits. In order to reduce the potential confusion between ESL signs and YOUR SPEED signs, and ensurethat the speed limit is considered a regulatory speed limit, the changeable display should be comprised of white LEDs.
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