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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

Interpretation Response #08-0046 ([Mr. Stanley Peterburgsky])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Stanley Peterburgsky

Location State: NY Country: US

View the Interpretation Document

Response text:

June 12, 2008

Mr. Stanley Peterburgsky

530 West 186th Street

New York, New York 10033

Ref. No. 08-0046

Dear Mr. Peterburgsky:

This responds to your e-mail regarding the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to flameless heaters used to warm packaged meals for human consumption. You ask whether previously issued de minimus interpretations (Ref. No. 98-0345 issued on March 3, 1999; Letter to Department of Defense issued on July 7, 1992) for certain flameless heaters are still valid and under what conditions. Additionally, you ask whether the meals may be warmed in-flight by a passenger if the heaters are not subject to the HMR.

The flameless heater you describe is manufactured by Innotech Products, Ltd. (Innotech) and contains a maximum of eight grams of a magnesium-iron alloy (as magnesium powder). Innotech"s Material Safety Data Sheet indicates that the magnesium alloy contained in its flameless heaters meets the definition of a Division 4.3 (Dangerous When Wet) material. The salt water catalyst for the heater is securely packaged separately within the meal carton. Each meal carton contains one heater and one water packet.

The previously issued interpretations you cite in your inquiry remain valid. A flameless heater containing eight grams or less of a magnesium-iron alloy (as magnesium powder) is in a quantity and form that does not pose a hazard in transportation and, thus, is not subject to the HMR. This exception does not apply to a heater that is packaged separately from a meal or a heater that contains more than eight grams of magnesium powder within a meal carton.

The Transportation Security Administration (TSA) is the agency responsible for security in all modes of transportation, including civil aviation, and has the authority to restrict passengers from carrying materials perceived as security threats. We note that the Internet website belonging to the company that markets the meals you wish to consume in-flight

cautions its customers not to activate the flameless heater on an airplane. For information about items that may be prohibited by the TSA, you should contact the TSA"s Contact Center directly by telephone at (866) 289-9673 or by e-mail at:

I trust this satisfies your inquiry. Please contact us if we can be of further assistance.


Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.124 Class 4, Divisions 4.1, 4.2 and 4.3-Definitions