Hazardous material
Hazardous material (HAZMAT) is a substance or material the Secretary of Transportation determines to be an unreasonable risk to health, safety, and property when transported in commerce, and labels as hazardous under section 5103 of the Federal Hazardous Materials Transportation Law (49 U.S.C. 5103 et seq.). When transported internationally hazardous material may be classified as Dangerous Goods. All such freight must be marked in accordance with applicable regulations and the carrier must be notified in advance.