Transportation of flameless ration heaters
Pipeline and Hazardous Materials Safety Administration · Jun 6, 2017 · Reference No. 17-0002
Interprets: 49 CFR § 173.22
Reggie’s quick take
Someone asked whether individual operational rations, such as MREs, that contain a flameless ration heater with 8 grams or less of magnesium alloy are subject to the Hazardous Materials Regulations. PHMSA said they are not, regardless of how many MREs go in one package. This applies to the rations as packed. It does not cover heaters shipped separately from the rations that are not hermetically sealed, or heaters with more than 8 grams of magnesium alloy, which must follow the HMR. Because the rations are not regulated, no shipping paper, safety data sheet, or other hazard communication is required under the HMR (see § 171.1 and related parts).
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 letter is in response to your December 29, 2016, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the transportation of flameless ration heaters (FRH) as a component packaged into individual operational rations. In your letter and subsequent phone call, you describe and provide safety data sheets (SDS) for certain Individual Operational Rations, including, but not limited to Meal, Ready-to-Eat (MRE) that are packed with an FRH containing 8 grams of magnesium alloy.
We have paraphrased and answered your questions as follows:
Q1. You ask whether Individual Operational Rations packed with an FRH that contains 8 grams of magnesium alloy or less is subject to the HMR as a hazardous material.
A1. PHMSA regulates the transportation in commerce of materials in an “amount and form [that] may pose an unreasonable risk to health and safety or property.” 49 U.S.C 5103, as delegated to PHMSA in 49 C.F.R 1.53(b). This Office determined in Ref. No. 08-0046 that an MRE packed with an FRH
containing 8 grams or less of magnesium alloy is not in a quantity and form that poses an unreasonable risk to health, safety, or property during transportation regardless of the number of MREs in a package. This interpretation remains valid. Therefore, Individual Operational Rations, such as MREs, are not subject to the HMR. Please note that this determination does not apply to FRH devices shipped separately from Individual Operational Rations that are not hermetically sealed or to FRH devices containing more than 8 grams of magnesium alloy, which must be shipped in conformance with the applicable requirements of the HMR.
Q2. You ask if an SDS for the magnesium alloy needs to accompany shipments of MREs that contain
an FRH.
A2. The HMR does not require an SDS to accompany a shipment of hazardous materials. In addition, based on the above determination, no other documentation or hazard communication requirements of the HMR apply.
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.