The U.S. Department of Transportation (DOT) has developed a list of hazardous materials that have been determined to pose an unreasonable risk to health, safety, and property when transported in commerce by air, highway, rail, or water. To readily convey information about the hazardous material and the risks it poses during transportation, DOT has developed specifications for labels, placards, and markings, as discussed in this section, that must be prominently displayed on each container or package, and on each transport vehicle.