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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 #07-0176 ([Missouri Gas Energy] [Ms. Crystal Callaway])

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

Interpretation Response Details

Response Publish Date:

Company Name: Missouri Gas Energy

Individual Name: Ms. Crystal Callaway

Location State: MO Country: US

View the Interpretation Document

Response text:

OCT 1, 2007

Ms. Crystal Callaway                             Ref. No. 07-0176

Missouri Gas Energy

3420 Broadway

Kansas City, MO 64111

Dear Ms. Callaway:

This responds to your August 29, 2007 letter requesting clarification of requirements for transport of manufactured articles containing mercury under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether gas meters with switches containing mercury transported in accordance with § 173.164(c)(2) are subject to the HMR. Additionally, you request a definition of "subchapter" as it pertains to § 173.164(c)(2).

You state that your company transports gas meters with an electronic device containing a small mercury switch attached to each gas meter. You also state each switch contains 1.16 g (0.04 ounces) of mercury.

Based on the information provided, the gas meters would not be subject to the requirements of the HMR. In accordance with § 173.164(c)(2), "thermometers, switches and relays, each containing a total quantity of not more than 15 g (0.53 ounces) of mercury, are excepted from the requirements of the subchapter if installed as an integral part of a machine or apparatus and so fitted that shock of impact damage, leading to leakage of mercury, is unlikely to occur under conditions normally incident to transport."

Regarding the definition of "subchapter" as it pertains to § 173.164(c)(2), "subchapter" refers to the regulations contained in Title 49, Subtitle B, Chapter I, Subchapter C, Parts 171-180 of the Code of Federal Regulations (CFR), more commonly referred to as the Hazardous Materials Regulations (HMR).

I hope this information is helpful. Please contact us if you require additional assistance.


John A. Gale

Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.164 Mercury (metallic and articles containing mercury)