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Interpretation Response #18-0141

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

Interpretation Response Details

Response Publish Date:

Company Name: Onepoint4 Ltd.

Individual Name: P. Shelly BEng (Hons)

Location State: Northumberland Country: GB

View the Interpretation Document

Response text:

May 09, 2019

P. Shelley BEng (Hons), MISEE, MIExpE
Managing Director
Onepoint4 Ltd.
75 Chevington Green,
Morpeth, Northumberland
NE65 9AX United Kingdom

Reference No. 18-0141

Dear Mr. Shelley:

This letter is in response to your October 26, 2018, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the classification of explosives.

We have paraphrased and answered your questions as follows:

Q1. You ask who is responsible for classifying explosive and pyrotechnic substances and articles in the United States.

A1. In accordance with § 173.56 of the HMR, classification of Class 1 (explosive) materials is the responsibility of the person who offers a new explosive and the examining agency and is subject to PHMSA's approval. Section 173.56 of the HMR specifies that an approval request must be submitted to the Associate Administrator of Hazardous Materials Safety with a classification report recommendation from an authorized test lab or a foreign competent authority approval that assigns a Division, compatibility group, and shipping description. If PHMSA finds that the approval request meets the regulatory criteria, the explosive will be approved in writing and assigned an EX number.

Q2. You ask whether the United States has an equivalent to Notified Bodies (NB; entities that are approved to carry out tests and classify explosives and pyrotechnics in the European Union).

A2. The answer is yes. Only approved examination agencies are permitted to carry out these tests and make a recommendation for Division, compatibility group, and shipping description. However, PHMSA ultimately approves the recommended classification, as indicated by the assignment of an EX number.

Q3. You ask whether manufacturers, suppliers and/or distributors are permitted to self-certify products in the United States.

A3. The answer is no. Self-certification is not permitted for Class 1 materials. Except for explosives made under the supervision of a component of the Department of Defense (DOD) or the Department of Energy (DOE), all new explosives must be approved by PHMSA or—for fireworks—an approved third-party agency (e.g., fireworks certification agency.)

Q4. In the event organizations are permitted to self-certify (see Q3), you ask for clarification of the rules and quality checks they must abide by (i.e., audits, equipment calibration, test standards, etc.)

A4. See A3. Self-certification is not permitted for Class 1 materials.

Q5. You ask whether there have been recent discussions on the classification for transport of Thermite (Iron Oxide and Aluminum).

A5. There have been extensive discussions surrounding the transport classification of thermites (broadly defined) and thermite derivatives.

Q6. You ask whether a Thermite composition that contains additional oxidizers, energetic binders and fuels, such as magnesium (i.e., a Thermate), would be classified under the "practical pyrotechnic effect" in the UN test matrix figure 10.2 of the UN Manual of Tests and Criteria. You further ask if there are any records of such classifications.

A6. Thermites and Thermates would both provide a "practical pyrotechnic effect" as defined by the UN Manual of Tests and Criteria. This Office is not aware of any public reports of such test results available at this time.

Q7. You ask whether there have been any tests carried out in accordance with the UN series of tests where Thermates were found to be more sensitive to dropping, thermal, electrostatic discharge, friction, impact, pressure and effects of shelf life, similar to Magnesium, Teflon, Viton (MTV) flare compositions.

A7. There are no widely available public data on the performance of Thermates.

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


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.56 New explosives-definition and procedures for classification and approval