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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Is Anhydrous Ammonia covered under the Hazardous Materials Safety Permit Program?

Due to Anhydrous Ammonia (ammonia, anhydrous) having both international and domestic entries in the Hazardous Materials Table (HMT)(See 49 CFR § 172.101), considerations must be made in order to determine the need for a Hazardous Materials Safety Permit (HMSP):

  • For Anhydrous Ammonia in “domestic transportation” (See 49 CFR § 171.8)  and described as UN1005 ammonia, anhydrous 2.2 Inhalation Hazard, an HMSP is not required.
  • For Anhydrous Ammonia described as UN1005, ammonia, anhydrous 2.3 Poison Inhalation Hazard or Toxic Inhalation Hazard, Zone D, and when transported in a packaging having a capacity greater than 13,248 L (3,500 gallons), an HMSP is required.  In these instances, Anhydrous Ammonia meets the definition of a Material that is Poison-By-Inhalation or Toxic-By-Inhalation as defined in 49 CFR § 171.8 and meets the criteria for a hazard zone D as specified in 49 CFR § 173.116(a).

Last Updated : August 29, 2017