Glossary DOT Hazmat Transportation



Administrator means the Administrator, Pipeline and Hazardous Materials Safety Administration.

Adsorbed Gas

Adsorbed gas means a gas which when packaged for transport is adsorbed onto a solid porous material resulting in an internal receptacle pressure of less than 101.3 kPa at 20 °C and less than 300 kPa at 50 °C.


Aerosol means an article consisting of any non-refillable receptacle containing a gas compressed, liquefied, or dissolved under pressure, the sole purpose of which is to expel a nonpoisonous (other than a Division 6.1 Packing Group III material) liquid, paste, or powder and fitted with a self-closing release device allowing the contents to be ejected by the gas.

Agricultural Product

Agricultural product means a hazardous material, other than a hazardous waste, whose end use directly supports the production of an agricultural commodity including, but not limited to a fertilizer, pesticide, soil amendment or fuel. An agricultural product is limited to a material in Class 3, 8 or 9, Division 2.1, 2.2, 5.1, or 6.1, or an ORM-D material.

Aircraft Battery

Aircraft battery means a battery designed in accordance with a recognized aircraft battery design standard (e.g., FAA technical standard order) that is capable of meeting all aircraft airworthiness requirements and operating regulations.


Approval means a written authorization, including a competent authority approval, issued by the Associate Administrator, the Associate Administrator's designee, or as otherwise prescribed in the HMR, to perform a function for which prior authorization by the Associate Administrator is required under Subchapter C of this chapter (49 CFR Parts 171 through 180).


Approved means approval issued or recognized by the Department unless otherwise specifically indicated in the HMR.

Asphyxiant Gas

Asphyxiant gas means a gas which dilutes or replaces oxygen normally in the atmosphere.

Associate Administrator

Associate Administrator means the Associate Administrator for Hazardous Materials Safety, Pipeline and Hazardous Materials Safety Administration.

Atmospheric Gases

Atmospheric gases mean air, nitrogen, oxygen, argon, krypton, neon, and xenon.

Authorized Inspection Agency

Authorized Inspection Agency means:

  1. A jurisdiction which has adopted and administers one or more sections of the ASME Boiler and Pressure Vessel Code as a legal requirement and has a representative serving as a member of the ASME Conference Committee; or
  2. An insurance company which has been licensed or registered by the appropriate authority of a State of the United States or a Province of Canada to underwrite boiler and pressure vessel insurance in such State or Province.

Authorized Inspector

Authorized Inspector means an Inspector who is currently commissioned by the National Board of Boiler and Pressure Vessel Inspectors and employed as an Inspector by an Authorized Inspection Agency.