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Interpretation Response #11-0003 ([S.E. McDonough & Associates, Inc.] [Ms. Susan E. McDounough])

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

Interpretation Response Details

Response Publish Date:

Company Name: S.E. McDonough & Associates, Inc.

Individual Name: Ms. Susan E. McDounough

Location State: FL Country: US

View the Interpretation Document

Response text:

April 12, 2012


Ms. Susan E. McDonough
S.E. McDonough & Associates, Inc.
4921 Southfork Drive, Suite 1
Lakeland, FL 33813

Ref. No. 11-0003

Dear Ms. McDonough:

This responds to your letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the classification of a sample material with an unknown or suspected hazard. In your letter, you state that your consulting firm is willing to provide regulatory guidance (and possibly more) to clients who intend to offer for transportation dust samples to determine if they meet U.S. Environmental Protection Agency (EPA) or the National Fire Protection Association (NFPA) standards for combustible or explosive dust. You ask how the HMR apply to such a material being transported to a laboratory for testing and analysis. I apologize for the delay in responding and any inconvenience it may have caused. Your questions are paraphrased and answered as follows:

Q1. What HMR requirements are applicable, if any, to our client"s dust samples?

A1. Section l72.10l(c)(11), states that except for certain materials (e.g., a flammable solid as defined by the HMR), a shipper may assign a tentative shipping name, hazard class, and identification number to a material based on the shipper's knowledge of the material, the hazard precedence prescribed in § l73.2a, and defining hazard class criteria in Subchapter C. In this context, "tentative" means a temporary selection of a proper shipping name and hazard class used for a material until a more definite proper shipping name and hazard class can be assigned based on test data and analysis. With samples, exact physical and chemical properties of many materials may be unknown because concentrations of the components may vary from one shipment to the next. Therefore, the use of a tentative classification and proper shipping name is authorized. However, should a shipper obtain more specific data on the properties of the material, the hazard class and proper shipping name must be modified, as applicable.

Q2. Is it appropriate to assume the dust is "combustible" or "explosible" for HMR purposes?

A2. For purposes of the HMR, the term "explosible" is not used or defined. An explosive, as defined in § 173.50(a), means any substance or article, including a device, which is designed to function by explosion (i.e., an extremely rapid release of gas and heat) or which, by chemical reaction within itself, is able to function in a similar manner even if not designed to function by explosion, unless the substance or article is otherwise classed under the provisions of the HMR. Further, as specified in § 173.21(h), packages containing materials (other than those properly classed as an explosive) which will detonate in a fire are forbidden in transportation in commerce.

For purposes of the HMR, a readily combustible solid is one that meets the criteria specified in § 173.124(a)(3) when tested in accordance with the United Nations (UN) Manual of Tests and Criteria. The use of a tentative classification and proper shipping name is authorized for a packaged sample as specified in response A1 above.

Q3. What if we or our clients suspect that a dust sample does not meet any hazard class as defined by the HMR but elect to have it tested anyway for Occupational Safety and Health Administration (OSHA) compliance?

A3. If you can ascertain without testing that a sample does not meet any hazard class as defined by the HMR, the sample is not subject to the HMR. Otherwise, a tentative classification must be issued in accordance with response A1 above.

Q4. Is there an "exempt quantity" that would exempt our clients from labeling the package or providing shipping papers when offered for transportation by highway or rail?

A4. Yes. For example, exceptions from the labeling and shipping paper requirements for limited quantities of Divisions 4.1 and 4.3 materials in Packing Groups II and III when offered for transportation by highway or rail are prescribed in § 173.151.

Q5. Do our clients require training as prescribed in § 172.704 of the HMR?

A5. Yes, if they are performing any regulated function (e.g., signing a shipping paper) subject to the requirements of the HMR.

Q6. If I am trained as required by the HMR, may I guide my clients through the shipping process without them being trained as well?

A6. No. See response A5 above.

Q7. I have tentatively selected "Metal powders, flammable, n.o.s. (Sample)" and "Flammable solid, inorganic, n.o.s. (Sample)" as proper shipping names for my client"s dust samples. Is this correct?

A7. Under § 173.22 of the HMR, it is the shipper"s responsibility to select the most appropriate description for a hazardous material based on its knowledge of the material. This Office does not normally perform that function. However, your selection appears appropriate based on the limited amount of information received with your inquiry.

Q8. We assigned Packing Group II to a dust sample package. Should we have selected Packing Group III instead?
A8. Not necessarily. See response A7 above.

Q9. Some of our clients are aware of the specific constituents that make up their dust samples (e.g., zinc dust, titanium). Should we recommend they use proper shipping names specifically listed in the § 172.101 Hazardous Materials Table (HMT) for their samples or should they use the generic descriptions instead?

A9. Unless specified otherwise in § 172.101(c)(12), a generic description should only be selected if the specific technical name for the substance or article is not listed in the HMT.

I trust this satisfies your inquiry. Please contact us if we can be of further assistance.



T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

172.101, 173.2a,

Regulation Sections

Section Subject
173.22 Shipper's responsibility