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Interpretation Response #09-0301 ([Tronox, LLC] [Mr. John Hatmaker])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Tronox, LLC

Individual Name: Mr. John Hatmaker

Location State: OK Country: US

View the Interpretation Document

Response text:

April 28, 2010




Mr. John Hatmaker

Director-Environment, Health & Safety

Tronox, LLC

P.O. Box 268859

Oklahoma City, OK 73126-8859

Ref. No.: 09-0301

Dear Mr. Hatmaker:

This responds to your e-mail regarding classification under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) of "Flameless Ration Heater" (FRH) containing a new formulation for providing hot meals to soldiers in the field, such as meals-ready-to-eat (MRE). Several attachments were included.

According to your letter, the Department of Defense (DOD) transports "Unitized Group Ration-Express" (UGR-E) for providing hot meals to soldiers in the field. This unit is capable of heating a meal that feeds 18 soldiers. The heating element in this unit is a "Flameless Ration Heater" (FRH). Currently, the FRH used in the UGR-E contains magnesium-iron alloy powders that are activated by aqueous sodium chloride to generate sufficient thermal energy to heat the food rations to 140-150ºF. The Mg/Fe based FRH generates substantial amounts of flammable gases when tested with distilled water in accordance with the UN Manual of Tests and Criteria, to meet the definition of Packing Group I or II in Class 4, Division 4.3.

Again according to your letter, your client has developed a new formulation for the FRH. This formulation was tested by an accredited laboratory, following the procedures in the UN Manual of Tests and Criteria. The test results indicate that the client's ration heater composition is not a Division 4.3 (Dangerous When Wet) material, and the results from an oxidizer test, UN Test Method O.1, classed the material as a Division 5.1 (Oxidizer), Packing Group III, as defined by the UN/DOT criteria. You state that you understand that in accordance with the requirements in § 173.22 of the HMR, it is the responsibility of the shipper to properly class a hazardous material. You request PHMSA"s approval to ship this new material formulation as an unregulated material, given its attached supporting documentation.

Based on the information you provided, it is the opinion of this Office that your client's FRH device containing not more than 70-80% manganese dioxide, 5-18% magnesium, and 2-25% carbon black meets the definition of a Division 5.1 (Oxidizer) material, as detailed by the results of UN Test Method O.1. Your client's FRH is regulated for purposes of transportation in commerce and must be shipped in conformance with the applicable requirements of the HMR and, therefore, may not be shipped as an unregulated material.

I hope this information is helpful. If we can be of further assistance, please contact us.


Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.22 Shipper's responsibility