Responsibility of Classifying Materials
Pipeline and Hazardous Materials Safety Administration · Aug 13, 1998 · Reference No. 98-0201
Interprets: 49 CFR § 173.22
Reggie’s quick take
A gas company asked whether PHMSA would confirm that its gas mixture was classified correctly, because an overseas customer wanted that documentation. PHMSA's answer is that under § 173.22 the shipper must classify the material itself, and the agency does not have to verify that classification. The manufacturer is generally expected to classify the material before its first shipment. The letter then starts to note that the company gave no specific information about the mixture, but it cuts off before saying what that means.
Written by AI (Claude) on Oct 22, 2026. Robots make mistakes and leave things out, so the letter below is what counts. Not legal advice.
This is in response to your letter dated July 20, 1998, requesting clarification on the proper classification of your gas mixtures under the Hazardous Materials Regulations (HMR.; 49 CFR Parts 171-180). Specifically, as stated in your letter, an overseas customer is requesting that you furnish documentation from this Department to confirm that Spectra Gases, Inc. has correctly classified the gas mixture in question.
Under 49 CFR 173.22, it is the shipper's responsibility to properly classify a hazardous material. Such determinations are not required to be verified by this Office. Generally, the manufacturer of a material has the knowledge to properly classify and is required to properly classify the hazardous material prior to initial shipment. Since you did not include any specific information
A letter of interpretation applies the regulations to the facts the requester described. It isn’t a regulation and isn’t legal advice. The agency’s copy.