PHMSA Response Letter

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Ms. Erin N. Jarman
Environmental Scientist
URS Corporation
1600 Perimeter Park Drive
Morrisville, NC 27560

Ref. No. 08-0193

Dear Ms. Jarman:

This is in response to your July 24, 2008 letter requesting further clarification of our letter to you dated June 20, 2008 concerning the packaging requirements for transporting non-pressurized gas under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

In your April 28, 2008, you asked whether shipping gas samples in “Tedlar” bags placed in a one-quart metal can (similar to a paint can) with a friction lid sealed with plastic-ring seals is permissible under the HMR. You also provided a copy of the product documentation for the friction lid metal cans indicating a hydrostatic test rating of 100kPa. In your most recent letter, you ask whether our response is the same if the hydrostatic test rating is 95 kPa instead of 100 kPa.

The answer is yes. Section 173.306(a)(4)(iii) requires non-pressurized gases, flammable to be packed in hermetically sealed glass or metal inner packagings of not more than 5 L (1.3 gallons) and overpacked in a strong outer packaging. Section 171.8 defines “hermetically sealed” as closed by fusion, gasketing, crimping, or equivalent means, so that no gas or vapor can enter or escape. It is the opinion of this Office that a metal can with a hydrostatic test rating of 95 kPa and a friction lid sealed with plastic-ring seals as described in your letter meets the definition of “hermetically sealed,” and therefore can be used as an inner packaging as specified in § 173.306(a)(4)(iii).

I hope this information is helpful.

Sincerely,

Susan Gorsky,
Acting Chief, Standards Development
Office of Hazardous Materials Standards

173.306(a)(4)(iii)