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Section §172.332: Identification number markings

Below are the available interpretations and guidance for the given section. To return to the list of parts, use the Parts link above. If you do not see any guidance or interpretation information below, that means there is none available for the given part/section. Return to the search page to browse additional regulations sections.

PHMSA has published several Frequently Asked Questions (FAQ) documents on regulatory topics. Please review our FAQ documents below:

Additionally PHMSA has Hazardous Materials FAQs based on letters of interpretation on the following topics:

This section of the website provides the ability to find regulations information including regulations parts, content of sections, and interpretations for regulations sections. Below is a list of parts, identified by the part number and subject. To browse sections by part, click on the subject link below. You will be taken to the eCFR website to view sections for a part.

A written regulatory interpretation, response to a question, or an opinion concerning a pipeline safety issue may be obtained by submitting a written request to the Office of Pipeline Safety (PHP–30), PHMSA, U.S. Department of Transportation, 1200 New Jersey Avenue SE., Washington, DC 20590–0001 or at the email address: In addition to email address, the requestor must include his or her return address and should also include a daytime telephone number. Requests should be submitted at least 120 days before the time the requestor needs a response.

Note: electronic submission is provided as alternative to the 49 CFR Part 190.11(b) mail-in requirement.

The regulations text of the section can be found on the eCFR website. To view the regulations text, use the link below. For assistance, please send an email to

View section 172.332 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
21-0059 XPO Logistics Ms. Marie Copeman View
21-0099 Lithium Battery Service GbR Eva Glimsche View
19-0116 Robert Lewis View
18-0075 MH Group, LLC Paul Perez View
18-0096 HOMENERGY Services, Inc Dan Reilly View
18-0005 Commerical Vehicle Safety Alliance Collin Mooney View
10-0182 J.J. Keller & Associates, Inc. Mr. Thomas Ziebell View
15-0166 ICC Compliance Center Ms. Sändra Miller View
03-0154 Brenntag Mid-South, Inc. Mr. A.B. Eargood View
08-0175 GEO Specialty Chemicals Mr. Matt Beasley View
15-0120 Daniels Training Services Daniel Stoehr View
14-0183 Denton Police Department Mr. William Burson View
16-0020 Nebraska State Patrol Sgt. Brad Wagner View
16-0177 Robinson Nevada Mining Company Mr. Matt Thompson View
06-0245 Reagent Chemical & Research, Inc. Mr. Robert Dritschel View
09-0171 Carus Corporation Mr. Chithambarathanu Pillai View
11-0291 Environmental Management, Inc. Jamie Newton View
01-0286 ChemTreat, Inc. Mr. John Mardigian View
16-0004 Texas Department of Public Safety Trooper Kelley F. McClatchy View
16-0004 Texas Department of Public Safety Trooper Kelly F. McClatchy View