The Effectiveness and Safety of Non-Traffic-Related Messages on Changeable Message Signs (Technical Summary)

Changeable message signs are electronic devices used along roadways to provide drivers with guidance related to traffic conditions and other events. Displayed messages can suggest that drivers take alternate routes in response to congestion, accidents or roadwork zones. CMSs are also used to display time-critical information not related to traffic control, such as Amber alerts regarding child abductions, as well as messages not specific to a time or roadway condition, such as “Don’t Drink and Drive.”