Changeable message signs (CMS) are used to communicate accurate, timely, and pertinent information to travelers on Kentucky’s roadways. This information helps travelers avoid hazards or delays and respond properly to changing roadway conditions. In an ideal environment, the Kentucky Transportation Cabinet (KYTC) would be able to allocate CMS to various areas of the state based upon changing needs. The location of each sign would be monitored, and the message could be controlled and checked remotely.

Currently these capabilities do not exist. KYTC has four different types of portable CMS in use throughout the state. Each type has different internal and external interfaces, and each requires different replacement parts. Also, there is no policy or guidelines in place for the use of these signs. The decision on how and when the CMS are used is made at the district level on a case-by-case basis.

This research effort includes an evaluation of Kentucky’s current inventory and usage of CMS, identification of key issues associated with the signs, and identification of state and regional policies on the management and use of CMS. Recommended guidelines for the management and use of CMS are included in this report.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky or the Kentucky Transportation Cabinet. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names is for identification purposes and is not to be considered an endorsement.