Which agency is primarily responsible for regulating hazardous materials transportation in the United States?

The Department of Transportation (DOT) is the agency primarily responsible for regulating hazardous materials transportation in the United States. This includes overseeing the safe transport of these materials across various modes of transportation such as road, rail, air, and sea. The DOT establishes regulations that govern the packaging, labeling, and handling of hazardous materials to ensure public safety and environmental protection during transportation.

In addition to the DOT’s role in regulatory oversight, it collaborates with other agencies, such as the Environmental Protection Agency (EPA), which focuses more on environmental protection aspects rather than transportation. Similarly, the Occupational Safety and Health Administration (OSHA) is concerned with workplace safety and health, while the Nuclear Regulatory Commission (NRC) oversees the safety of nuclear materials but does not directly regulate hazardous materials transportation in general. The DOT's comprehensive frameworks and guidelines make it the authoritative body in the transportation of hazardous materials.