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Interpretation Response #10-0088 ([Dyno Nobel, Inc.] [Mr. Mark Anderson])

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

Interpretation Response Details

Response Publish Date:

Company Name: Dyno Nobel, Inc.

Individual Name: Mr. Mark Anderson

Location State: CT Country: US

View the Interpretation Document

Response text:

June 3, 2010





Mr. Mark Anderson

Dyno Nobel Inc.

660 Hopmeadow

P.O. Box 2006

Simsbury, CT 06070

Ref. No.: 10-0088

Dear Mr. Anderson:

This responds to your e-mail dated April 20, 2010 regarding the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) as they apply to reduced size hazard warning labels for Class 1 (Explosives). You did not enclose a diagram or photograph depicting the orientation of the Class 1 (Explosives) label nor the dimensions of the box. Subsequently, an inspector provided photographs of orientation of the Class 1 (Explosives) label on the box.

According to your letter, during an inspection, several DOT inspectors questioned whether a square-on-point (diamond) reduced size label meets the requirements of the HMR, and said that it should be rotated 90º. You believe that the rotation of the diamond shaped hazard warning label 90º would misrepresent the product to emergency responders, as the diamond shape makes it identifiable as a hazardous material package. You ship these packages internationally to other countries that do not accept a hazard warning label rotated 90º on its side. Several boxes used to transport your company"s Class 1 (Explosives) products are shorter in height than the square-on-point or diamond shaped 100 mm (3.9 inches) hazard warning label. You ask whether your understanding is correct that §172.407(f) allows use of a reduced size hazard warning label that conforms to the UN Recommendations.

The labeling specifications provided in §172.407(c) of the HMR require each hazard warning label to be at least 100 mm (3.9 inches) on each side. The provisions in §172.406(b)(1) and (3) specify that a label may be printed on or placed on a securely affixed tag or may be affixed by other suitable means to: (1) a package that contains no Class 7 (Radioactive) material which has dimensions less than those of the required label; and (2) a package which has an irregular surface that a label cannot be satisfactorily affixed. The UN Recommendations ( specify that a hazard warning label must be in the form of a square set at an angle of 45º (diamond-shaped) with minimum dimensions of 100 mm X 100 mm (3.9 inches), except in the case of packages of such dimensions that they can only bear small labels, as provided in

The HMR do not prohibit the placement of a hazard warning label (e.g., Class 1 (Explosives)) in an orientation where the square-on-point is located with its flat sides parallel to the sides of the packages. That is, the label may be placed square-on-side when the square-on-point is not practicable. In accordance with §172.407(f) of the HMR, except for materials poisonous by inhalation, a label conforming to specifications in the UN Recommendations may be used in place of a corresponding label that conforms to the requirements of the HMR, which permit use of a reduced size hazard warning label when a package surface is too small or of an irregular shape for a full size label. Therefore, you may use a reduced size hazard warning label that conforms to the UN Recommendations.

I hope this information is helpful. If we can be of further assistance, please contact us.


Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards

cc: Bob Burns, PHH-40

Edward Ratstetter, PHH-40

John Henegan, PHH-40

172.407(c), 172.406(b)(1)

Regulation Sections

Section Subject
172.406 Placement of labels
172.407 Label specifications