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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 #99-0265 ([Mr. Timothy H. Shaw])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Timothy H. Shaw

Location State: MI Country: US

View the Interpretation Document

Response text:

January 28, 2000


Mr. Timothy H. Shaw                   Ref. No. 99-0265
484 West Main Street
Milan, MI 48160

Dear Mr. Shaw:

This is in response to your letter dated September 25, 1999, regarding the requirement for showing the letters, “UN” on shipping documents under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you ask if the notification to the Pilot-in-Command may omit the letters “UN” before the corresponding hazardous material identification number.

The answer is no.  Section 175.33 (a)(1), Notification of pilot-in-command, requires that the notification to the pilot contain the identification number of the material as specified in § 172.101, Hazardous Materials Table (HMT), or the International Civil Aviation Organization’s (ICAO) Technical Instructions.  Section 4.1.2 of Part 4, Chapter 4 of the ICAO Technical Instructions requires that an identification number be preceded by the letters “UN.”

It is the opinion of this Office that the information provided to the Pilot-in-Command, as specified in
4.1.1 of Part 5, Chapter 4 must be consistent with the documentation requirements identified in the paragraph above.

I hope this satisfies your request.



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


Regulation Sections

Section Subject
175.33 Shipping paper and notification of pilot-in-command