Automated flagger assistance devices (AFADs) are designed to be remotely operated by aflagger positioned outside of the travel lane, thereby reducing their exposure to vehicular traffic.There are two types of AFADs. One type uses a remotely controlled stop/slow sign toalternately control the right-of-way. The other type uses remotely controlled red and yellowlenses and a gate arm to alternately control the right-of-way. While AFADs may increase thesafety of flaggers, there were concerns that motorists may misunderstand AFADs; thus,increasing the potential for motorists to enter the lane closure under the stop condition. As partof a recent Texas Department of Transportation project, Texas Transportation Instituteresearchers conducted field studies at lane closures on two-lane, two-way roadways in Texas toassess the operational and safety effectiveness of AFADs relative to the use of flaggers.The research findings show that some motorists may misunderstand the directionsprovided by AFADs and enter the lane closure under the stop condition. The violation rate forthe stop/slow AFAD without a gate arm was the highest and was significantly higher than theviolation rate for the red/yellow lens AFAD (which requires a gate arm). Adding a gate arm tothe stop/slow AFAD decreased the violation rate such that it was not significantly different fromthe red/yellow lens AFAD. In addition, alternative supplemental signs increased motoristunderstanding that the stop sign would change to a slow sign when motorists were allowed toproceed.
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