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Interpretation Response #13-0228 ([HMT Associates, LLC] [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, LLC

Individual Name: Mr. E. A. Altemos

Location State: VA Country: US

View the Interpretation Document

Response text:

February 12, 2014

Mr. E. A. Altemos
HMT Associates, LLC
603 King St., Suite 300
Alexandria, VA  22314-3105

Ref. No. 13-0228

Dear Mr. Altemos:

This responds to your November 22, 2013 letter requesting clarification of the applicability of the air transport requirements for friction-type closures under the hazardous materials regulations (HMR; 49 CFR Parts 171-180).  Specifically, you seek confirmation that a “snap-type” cap for a marker pen is not considered a friction-type closure as used in
§ 173.167 of the HMR.

In your letter, you describe a marker pen (i.e., a marker) containing small quantities of free liquid meeting the criteria for a Class 3, packing group II, flammable liquid.  The marker is of such a design that the cap is secured to the barrel of the pen by means of “nubs” in the cap that securely engage grooves in the barrel.  The cap “snaps” securely into place indicating proper closure.  Furthermore, you point out that data show more than twice the force of an external vacuum subjected to the cap under atmospheric pressure is needed to remove the cap; and the minimum removal force in every case exceeds the force of the pressure differential.  In addition, vibration tests have demonstrated that the cap remains secure when subjected to vibrations typically encountered during the course of transportation.  

It is your understanding that the closure you describe is not considered a friction-type closure for purposes of transporting consumer commodities (ID8000) in accordance with
§ 173.167 (as well as Packing Instruction Y963 of the International Civil Aviation Organization Technical Instructions for the Safe Transportation of Dangerous Goods by Air) and therefore, is not subject to the requirement for a secondary means of securement applicable to friction-type closures.

Your understanding is correct.  A “snap-type cap” such as you describe in your letter would not be considered a friction-type closure for purposes of the § 173.167 requirements for consumer commodities transported by air and thus, is not subject to the requirement for a secondary means of securement under § 173.167(a).

I hope this information is helpful.  If you have further questions, please contact this office.


Robert Benedict
Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.167 Consumer commodities