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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 #23-0026

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

Interpretation Response Details

Response Publish Date:

Company Name: Transport Canada/Government of Canada

Individual Name: Mr. Kurt Sieloff

View the Interpretation Document

Response text:

August 6, 2024

Mr. Kurt Sieloff
Regional Transportation of Dangerous Goods Inspector
Transport Canada/Government of Canada
100 Princess Street, Unit 360
Thunder Bay, Ontario
Canada

Reference No. 23-0026

Dear Mr. Sieloff:

This letter is in response to your March 10, 2023, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to CG-7 pressure relief valves and the definition of industrial motor fuel. In your email, you reference § 173.301(f), which incorporates by reference Compressed Gas Association (CGA) publication S-1.1 (2011), and thus requires pressure relief devices to comply with the CGA pamphlet on pressure relief device standards.

We have paraphrased and answered your questions as follows:

Q1. You ask whether CG-7 pressure relief valves commonly found on 20, 40, 60, and 100 pound propane cylinders require requalification if they are not used in "industrial motor fuel" service.

A1. The answer is no. Paragraph 9.1.1 in CGA S-1.1 states that CG-7 pressure relief valves (other than those used in industrial motor fuel service) shall be replaced or requalified within 10 years of the valve's manufacture date. However, § 173.301(f)(1) states that "except as provided in paragraphs (f)(5) through (f)(7) and (j) of this section, and § 171.23(a) of this subchapter, a cylinder filled with a gas and offered for transportation must be equipped with one or more pressure relief devices sized and selected as to type, location, and quantity, and tested in accordance with CGA S-1.1 (compliance with paragraph 9.1.1 is not required) and CGA Pamphlet S-7 (IBR, see § 171.7 of this subchapter)." As noted in your incoming email, your CG-7 pressure relief valves meet the exception provided by § 173.301(f)(1) of not requiring requalification in paragraph 9.1.1 of CGA S-1.1.

Q2. You ask whether PHMSA can provide a definition for "industrial motor fuel."

A2. While there is no definition for "industrial motor fuel" in the HMR or CGA S-1.1, the intent behind paragraphs 9.1.1 and 9.1.2 of CGA S-1.1 was to correspond with National Fire Protection Agency (NFPA) publication 58, paragraph 5.9.2.14. This paragraph states that "all cylinders used in industrial truck service (including forklift truck cylinders) shall have the cylinder's pressure relief valve replaced by a new or unused valve within 12 years of the date of manufacture of the cylinder and every 10 years thereafter."

I hope this information is helpful. Please contact us if we can be of further assistance.

Sincerely,

Eamonn Patrick
Acting Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

171.7, 171.23(a), 173.301(f), 173.301(f)(1)

Regulation Sections