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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 #11-0032 ([RSLP, TASC Inc.] [Ms. Lisa Taylor])

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

Interpretation Response Details

Response Publish Date:

Company Name: RSLP, TASC Inc.

Individual Name: Ms. Lisa Taylor

Location State: UT Country: US

View the Interpretation Document

Response text:

June 9, 2011



Ms. Lisa Taylor


Hill AFB, B1267 West Side, UT

Reference No. 11-0032

Dear Ms. Taylor,

This is in response to your e-mail requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the display of identification numbers on Class 1 (explosive) placards. Specifically, you request confirmation of your understanding that motor vehicles may not display identification numbers on placards with for Division 1.1 and 1.3 (explosive) materials.

The limitations pertaining to the display of identification numbers (see § 172.503) on placards are set forth in § 172.334. Section 172.334(a) prohibits the display of an identification number on certain placards, including EXPLOSIVES 1.1, 1.2, 1.3, 1.4, 1.5 and 1.6 placards. However, as specified in § 172.336(b), for materials in hazard classes for which placards are specified and identification number displays are required, but for which identification numbers may not be displayed on the placards authorized for the material, identification numbers must be displayed on orange panels or on the plain white square-on-point display configuration in association with the required placards. An identification number displayed on a white square-on-point display configuration is not considered to be a placard.

I hope this information is helpful. Please contact this Office should you need additional assistance.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

172.336(b), 172.334, 172.503


Regulation Sections

Section Subject
172.334 Identification numbers; prohibited display
172.336 Identification numbers; special provisions
172.503 Identification number display on placards