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Interpretation Response #00-0226 ([Triangle Environmental Services] [Mr. Wayne Stollings])

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

Interpretation Response Details

Response Publish Date:

Company Name: Triangle Environmental Services

Individual Name: Mr. Wayne Stollings

Location State: NC Country: US

View the Interpretation Document

Response text:

September 25, 2000


Mr. Wayne Stollings                  Ref. No. 00-0226
Triangle Environmental Services
P.O. Box 13294
Research Triangle Park, NC 27709

Dear Mr. Stollings:

This is in response to your letter dated April II, 1997, and your follow-up letter dated July 31, 2000, requesting clarification on the shipment of landfill gas samples under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you request written confirmation of your hazard class analysis of these gas samples as discussed with Dr. George Cushmac, Office of Hazardous Materials Technology.

According to your letter, environmental gas samples from landfills are packaged in 4.5 and 8.3 liter stainless steel canisters.  The canisters are under a vacuum and can only be filled with sample to atmospheric pressure.  The samples have the potential to contain a significant amount of methane and carbon dioxide so the canisters are half filled with helium prior to sampling as requirements in U.S. EPA Method 25-C.  The maximum expected concentration of gases in the mixture contained at the time a shipment would be 50% helium, 25% carbon dioxide, 25% methane, and trace concentrations of
various organic compounds.

It is the shipper's responsibility to properly classify a hazardous material in accordance with § 173.22. This Office does not perform that function.  It is your understanding, based on your analysis of the gas samples and verbal confirmation from Dr. Cushmac, that the gas samples do not meet the hazard class defining criteria in Part 173 of the HMR for Division 2.3 poisonous gas materials or Division 2.1 flammable gas materials.  If your gas samples do not meet the defining criteria in Part 173, they are not subject to the HMR.

Section 173.306(a)(4) requires gas samples to be transported under the following conditions: (1) a gas sample may only be transported as non-pressurized gas when its pressure corresponding to ambient atmospheric pressure in the container is not more than 105 kPa absolute (I 5.22 psia); (2) non­pressurized gases, toxic (or toxic and flammable) must be packed in hermetically sealed glass or metal inner packagings of not more than one L (0.3 gallons) overpacked in a strong outer packaging; (3) non­pressurized gases, flammable must be packed in hermetically sealed glass or metal inner packagings of not more than 2.5 L (0.5 gallons) overpacked in a strong outer packaging.

I hope this satisfies your inquiry on environmental air samples.


Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards



Regulation Sections

Section Subject
173.306 Limited quantities of compressed gases