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Interpretation Response #21-0095

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

Interpretation Response Details

Response Publish Date:

Company Name: DynaEnergetics US Inc.

Individual Name: Mr. Ed Zinsmeyer

Location State: TX Country: US

View the Interpretation Document

Response text:

December 29, 2021

Mr. Ed Zinsmeyer
Compliance Manager AME
DynaEnergetics US Inc.
2050 West Sam Houston Parkway South
Suite 1750
Houston, TX  77042

Reference No. 21-0095

Dear Mr. Zinsmeyer:

This letter is in response to your September 20, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the classification of jet perforating guns (JPGs). Specifically, you state that your company has a JPG that was tested and approved by the Pipeline and Hazardous Materials Safety Administration (PHMSA) in accordance with § 173.56, but not classed using the Association of Energy Service Companies (AESC)/Institute of Makers of Explosives (IME) Standard, also known as the "Guide to Obtaining DOT Approval of Jet Perforating Guns using AESC/IME Perforating Gun Specifications," Ver. 02, dated September 1, 2017. You have included an Explosives Approval Letter, issued by PHMSA, which indicates the JPGs are classed as "UN0494, Jet perforating guns, charged, oil well, without detonator, 1.4D." You ask whether your JPGs may be transported without conforming to the requirements of Special Provision 114 in § 172.102.

The answer is yes. While Special Provision 114 provides conditions by which JPGs approved under UN0124, 1.1D may be reclassed to 1.4D under UN0454, it does not preclude the possibility of fully testing a JPG for approval as UN0454, 1.4D directly in accordance with § 173.56(b). The conditions of Special Provision 114 are applicable to JPGs PHMSA has approved as "UN0124, Jet perforating guns, charged, oil well, without detonator, 1.1D," and are not an additional requirement for those directly approved by PHMSA as "UN0494, Jet perforating guns, charged, oil well, without detonator, 1.4D."

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


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

172.102, 173.56, 173.56(b)

Regulation Sections

Section Subject
172.102 Special provisions
173.56 New explosives-definition and procedures for classification and approval