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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 #02-0057 ([Wegman, Hessler & Vanderburg] [John J. Geffer])

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

Interpretation Response Details

Response Publish Date:

Company Name: Wegman, Hessler & Vanderburg

Individual Name: John J. Geffer

Location State: OH Country: US

View the Interpretation Document

Response text:

February 28, 2002

Mr. John J. Geffert                 Reference No. 02-0057

Wegman, Hessler & Vanderburg

6055 Rockside Woods Blvd.

Cleveland, Ohio 44131-2302

Dear Mr. Geffert:

This is in response to your letter requesting clarification of the requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) regarding the term "securely closed" in § 173.220(b)(1). You state that your client wishes to transport a subcompact tractor that has a vented cap on the fuel tank.  The vented cap contains a valve that seals off the tank to prevent leakage of fuel in the event the tractor does not remain upright during transportation.  You ask whether a vented cap with a sealing valve is considered securely closed under the HMR.

Section 173.220(b)(1) and (b)(4) provides the requirements for transporting self-propelled vehicles containing flammable fuel.  The term "securely closed," as it applies to the vents in the cap, means that no flammable gas, vapor or liquid will be able to escape.  Securely closing the cap of the fuel tank without also securing vents in the cap does not satisfy the requirement in § 173.220. .

Sections 173.21(g) and 173.24 (f) and (g) also apply to the vented caps on the subcompact tractor.  Section 173.21(g) prohibits the offering for transportation or the transportation of packagings that give off a flammable gas or vapor likely to create a flammable mixture with air in a transport vehicle.  Section 173.24(f) requires closures on packagings to be secure and leakproof with no release of hazardous materials to the environment from the opening.  Section 173.24(g) permits venting to reduce internal pressure only under certain conditions, including when the evolved gases are not likely to

create a flammable mixture with air under normal conditions of transportation.  Thus, vents in a cap such as you describe must be securely closed to prevent the escape of gas or vapor.

I hope this information is helpful.  Please contact this office if you need additional information.


Susan E. Gorsky

Transportation Regulations Specialist

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.220 Internal combustion engines, vehicles, machinery containing internal combustion engines, battery-powered equipment or machinery, fuel cell-powered equipment or machinery