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Interpretation Response #01-0259 ([HMT Associates, L.L.C.] [Mr. E. A. Altemos])

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

Interpretation Response Details

Response Publish Date:

Company Name: HMT Associates, L.L.C.

Individual Name: Mr. E. A. Altemos

Location State: VA Country: US

View the Interpretation Document

Response text:

November 28, 2001


Mr. E. A. Altemos                           Reference No. 01-0259
HMT Associates, L.L.C.
603 King Street, Suite 300
Alexandria, VA 22314-3105

Dear Mr. Altemos:

This is in response to your inquiry, concerning the use of limited quantity markings authorized by the European Agreement for the Transport of  Dangerous Goods by Road (ADR).  These markings include a diamond displaying the letters “LQ” or a diamond with a UN number displayed.  You ask whether these markings would be acceptable on packages shipped by air within the United States under the provisions of the ICAO Technical Instructions for the Safe Transport of Dangerous Goods by Air (ICA0 TI).

Currently the Hazardous Materials Regulations (U.S. HMR;49 CFR Parts 100-185) prohibit markings which by their color, design, or shape could be confused with or conflict with labels required by 49 CFR (see 49 CFR 172.401). In a letter to the European Safety Institute dated February 20, 2001.  We stated the following:

In previous correspondence we have stated that we consider the ADR limited quantity markings to be confusing and prohibited from use by 49 CFR 172.401, which forbids markings which by their "color, design, or shape could be confused with or conflict with' labels required by 49 CFR.  However, the IMDG Code does not include a prohibition consistent with § 172.401. Furthermore, § 171.12 authorizes shipments which are made in accordance with the lMDG Code to be transported within the United States subject to the limitations of § 171.12. As the lMDG Code does not specifically prohibit the use of the labels authorized by the ADR, packages which are transported in accordance with the IMDG Code may be marked with the current ADR markings and are acceptable for transportation within the United States.

We recommended that the ADR-marked packages transported under the IMDG Code be limited to closed freight containers and transport vehicles in order to avoid potential frustration of shipments due to the markings not being recognized in the HMR.

The ICAO TI differ from the IMDG Code in that it is impracticable to expect that packages shipped in accordance with the ICAO TI would be in closed freight containers or transport vehicles for transport by air.  Also, the ICAO TI contain specific marking and labeling prohibitions (see Part 5, 2.4.11 and 3.2.13) for markings and labels which could be confused with or conflict with any of the markings and labels prescribed by the ICAO TI because of their color, design or shape.  Therefore, acceptability of the ADR markings under the two standards is not analogous.  Furthermore, it is our opinion that the ADR marking of a diamond containing an “LQ” mark is not acceptable under provisions of the ICAO TI and 49 CFR 171.1 1. The UN Committee of Experts on the Transport of Dangerous Goods did not adopt the diamond containing the “LQ” mark on the basis that it did not adequately convey sufficient information relative to the hazards posed by the substances contained in the packagings.

We have reconsidered the acceptability of the ADR marking of a diamond containing one or more UN nuriibers in light of the fact that this marking has been adopted in the LTN Recommendations.  Based on the language of 49 CFR 172.401 (c)(1), it is our opinion that this marking is not prohibited under the HMR and would be acceptable for use under the provisions of 49 CFR 171.11 and 171.12. We intend to propose inclusion of this marking in a future international harmonization rulemaking

I trust this is responsive to your inquiry.  If this office can be of further assistance, please contact us.



Edward T. Mazzullo
Director, Office of Hazardous
Materials Standards


Regulation Sections

Section Subject
171.12 North American Shipments