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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 #21-0030

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

Interpretation Response Details

Response Publish Date:

Company Name: Wellmatics

Individual Name: Joshua Howk

Location State: TX Country: US

View the Interpretation Document

Response text:

August 19, 2021

Mr. Joshua Howk
6770 McHard Road
Houston, TX 77053

Reference No. 21-0030

Dear Mr. Howk:

This letter is in response to your March 22, 2021, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to labeling and marking requirements for jet perforating guns (JPGs). You provide an overview of your JPG loading and preparation for transportation process and state that, when multiple JPGs are palletized, the required labels and markings are not always visible and/or may not be applied. Furthermore, you provide images of a potential solution; specifically, an extended threaded end cap design that would allow space for placement of the required label(s) and marking(s) without having to remove the JPG from a pallet. You ask whether the placement of a label and marking on the extended threaded end cap—for each individual JPG on a pallet—meets the labeling and marking requirements of the HMR.

The answer is yes. As provided in §§ 172.304 and 172.406, respectively, each marking must be printed on or affixed to the surface of a package or on a label, tag, or sign, and each label must be printed on or affixed to a surface (other than the bottom) of the package or containment device containing the hazardous material and near the proper shipping name marking.

Provided each individual JPG on a pallet is labeled and marked—either on the body of the JPG or on its extended threaded end cap—this practice would be in compliance with the HMR.

I hope this information is helpful. Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

172.304, 172.406

Regulation Sections

Section Subject
172.406 Placement of labels
173.304 Filling of cylinders with liquefied compressed gases