Transport of dangerous goods by air must be in accordance with United States' Regulations (49 CFR 171-180) or these Technical Instructions as limited by 49 CFR Part 171, Subpart C. The requirements of 49 CFR 175 apply to the offering, acceptance, and transportation of dangerous goods in commerce by aircraft to, from, or within the United States, and to any aircraft of United States' registry anywhere in air commerce. Part 175 contains additional requirements applicable to any person who performs, attempts to perform, or is required to perform a function subject to 49 CFR and is also applicable to air passengers and crew.

When the Technical Instructions are used for consignments of dangerous goods, failure to comply with the Technical Instructions and all relevant United States' variations is a violation of the United States' regulations

The appropriate national authority for the United States is:

- Associate Administrator for Hazardous Materials Safety
  Pipeline and Hazardous Materials Safety Administration
  U.S. Department of Transportation
  Washington, D.C. 20590-0001

English must be used for all required package markings and for the dangerous goods transport document. Abbreviations may not be used unless they are specifically authorized by these Instructions or by Subpart C and D of 49 CFR 172.

A copy of the transport document, or an electronic image thereof, must be retained by the shipper for not less than two years after the dangerous goods are accepted by the initial operator. Each shipping paper copy must include the date of acceptance by the initial operator, except that the date on the air waybill or bill of lading may be used in place of the date of acceptance by the initial operator. For a hazardous waste, the transport document must be retained for three years after the waste material is accepted by the initial operator.

- Note.- The United States' Regulations, as well as interpretations regarding their use, are available via the internet at http://www.phmsa.dot.gov/hazmat/regs. Questions regarding the Regulations may be directed to the Office of Hazardous Materials Safety Information Center at (800) 467-4922, (202) 366-4488 or by e-mail at infocntr@dot.gov.