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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #19-0055

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

Interpretation Response Details

Response Publish Date:

Company Name: Dangerous Goods Transport Consulting Inc.

Individual Name: Frits Wybenga

Location State: MD Country: US

View the Interpretation Document

Response text:

October 8, 2019

Frits Wybenga
Dangerous Goods Transport Consulting Inc.
15108 Red Clover Drive
Rockville, MD  20853

Reference No. 19-0055

Dear Mr. Wybenga:

This letter is in response to your April 17, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the reclassification of certain fire suppression systems as permitted by Special Permit (SP) DOT-SP 20600. Specifically, you ask a number of questions regarding PHMSA’s intent and authority as it relates to the issuance of the special permit and the provisions of the International Civil Aviation Organization Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICAO Technical Instructions).

PHMSA issued SP 20600 in accordance with 49 CFR Part 107, Subpart B to permit the transport of certain devices under alternative provisions to the requirements specified in the § 172.101 Hazardous Materials Table and § 173.166. Because PHMSA is the competent authority for the transportation of hazardous materials (dangerous goods) as cargo by air to, from, or within the United States, SP 20600 serves as a competent authority approval for the purposes of compliance with international transport standards and regulations. Note that under the HMR, the use of the ICAO Technical Instructions is optional, and although PHMSA has competent authority status, acceptance of a shipment authorized under PHMSA's authority is ultimately left to the discretion of the destination State.

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


Shane C. Kelley
Standards and Rulemaking Division

107, 172.101, 173.166

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.166 Safety devices