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Interpretation Response #21-0062

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

Interpretation Response Details

Response Publish Date:

Company Name: Institute of Makers of Explosives

Individual Name: Susan JP Flanagan

Location State: DC Country: US

View the Interpretation Document

Response text:

March 9, 2022

Susan JP Flanagan
Institute of Makers of Explosives
1212 New York Avenue, NW, Suite 650
Washington, DC  20005

Reference No. 21-0062

Dear Ms. Flanagan:

This letter is in response to your June 7, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to explosives classification (EX) approvals. Specifically, you ask for clarification on the impact of changes in corporate legal structure on the status of existing EX approvals and ask for clarification on the reciprocity of competent authority approvals authorized in the U.S. and Canada. You reference a Pipeline and Hazardous Materials Safety Administration (PHMSA) guidance document titled, EXPLOSIVES CLASSIFICATION (EX) APPROVALS (Company Name Changes, Mergers, Acquisitions, and Changes in Legal Structure), and provide two scenarios regarding: (1) the transportation of foreign-approved explosives through the U.S.; and (2) the transferability of a PHMSA-issued EX approval issued to a domestic company to a Canadian facility owned and operated by the same company.

For each scenario we have paraphrased and answered your questions as follows:

Scenario #1: Explosives products are manufactured in Canada and are authorized by the Canadian competent authority.

Q1. You ask whether these products may be transported through the U.S. to a destination outside of the U.S. without an EX approval.

A1. The answer is no. As specified in § 171.12(a), a hazardous material transported from Canada to the United States, from the United States to Canada, or transiting the United States to Canada or a foreign destination may be offered for transportation or transported by motor carrier and rail in accordance with the Transport Canada TDG Regulations as authorized in § 171.22, provided the requirements in §§ 171.22 and 171.23, as applicable, are met. Section 171.23(b)(4) specifically requires that, prior to being transported within the United States, Class 1 (explosive) materials must be approved by the Associate Administrator in accordance with § 173.56.

Q2. You ask whether these products may be transported into the U.S. to a distribution center for further distribution outside of the U.S. without an EX approval.

A2. The answer is no. See answer A1.

Q3. You ask whether these products may be transported into the U.S. for use within the U.S. without an EX approval.

A3. The answer is no. See answer A1.

Scenario #2: A U.S.-based manufacturer is contemplating manufacturing products at a company-owned facility in Canada. The products have received EX approvals from PHMSA for domestic manufacture and transportation. The products to be made in Canada would be:

  • manufactured to the same specifications as the EX-approved products;
  • manufactured using equipment comparable to that used to make the EX-approved products;
  • manufactured under the direction and supervision of the U.S. manufacturer; and
  • shipped to the U.S. manufacturer for distribution within the U.S. as well as export to other countries.

Q4. You ask whether the existing EX approvals apply, or would separate EX approvals be required for the products intended to be made in Canada.

A4. The answer is no, the existing EX approvals would not apply, Specifically, separate EX approvals are required. All manufacturing locations outside of the U.S. are required to apply for their own EX approval.

Furthermore, on October 8, 2019, PHMSA published a notice and request for comment [84 FR 53822] titled "Hazardous Materials: Clarification of Process to Reissue Explosives Classification Approvals." While the policies in the table of the guidance document EXPLOSIVES CLASSIFICATION (EX) APPROVALS (Company Name Changes, Mergers, Acquisitions, and Changes in Legal Structure) remain unchanged, the notice is part of PHMSA's efforts to update the guidance document while addressing stakeholder comments.

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

171.12(a), 171.22, 171.23, 171.23(b)(4), 173.56

Regulation Sections

Section Subject
171.12 North American Shipments
171.22 Authorization and conditions for the use of international standards and regulations
171.23 Requirements for specific materials and packagings transported under the ICAO Technical Instructions, IMDG Code, Transport Canada TDG Regulations, or the IAEA Regulations
173.56 New explosives-definition and procedures for classification and approval