The United States Coast Guard has published a free resource CD-ROM that brings comprehensive chemical information to the fingertips of fire and safety service personnel responding to a hazardous materials incident. Users can search the database by a substance's color, odor, and physical appearance and use the data to plan for a safe and effective response. Chemicals are rated according to health risk, flammability, and reactivity, among other factors, using data from several sources. The CD-ROM, known as CHRIS+, contains several databases of chemical, physical, thermodynamic, toxicological, and fire properties. Weapons of Mass Destruction (WMD) First Responder's Guide, the Coast Guard's advice for responders to WMD incidents.