The term “hazardous material” refers to any substance that could harm a worker, user, or bystander on its own or through interaction with another material. The United States government regulates the use and transportation of hazardous material within its own scope of influence. For example, the US Department of Transportation (DOT) regulates the transportation of potentially harmful substances, while the Occupational Safety and Health Administration (OSHA) oversees health or physical hazards in the workplace.
In regulating hazardous substances in the workplace, OSHA identifies materials that act directly on body systems, as well as those that can combust, explode, react, or release harmful fumes. The same organization also includes as hazardous substances those materials that can harm the environment if spilled or improperly dumped. The Department of Transportation, by contrast, classifies substances not by the harm that they do but by their particular makeup. These categories include flammable liquids, radioactive material, and corrosive material. Although other agencies have different definitions of hazardous material, each approaches the regulation process with an eye toward preventing harm.