For example, if emergency responders arrive at the scene of an overturned tractor trailer displaying a DOT hazmat placard, they would use the guide to identify the material associated with the placard and get guidance on how to respond accordingly. The 2020 version of the ERG includes general revisions, reorganized general information pages, protective distance mapping updates, and the new ability to share data links through URLs. Updated every four years, the ERG is available free to public safety agencies in all states and territories through designated state coordinators’ offices. PHMSA has partnered with the National Library of Medicine to provide this free application as well as a version of the ERG in its Wireless Information System for Emergency Responders (WISER) application.