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Section §172.336: Identification numbers; special provisions

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 172.336 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
21-0008 Railsback HazMat Safety Professionals, LLC Rex C. Railsback View
18-0075 MH Group, LLC Paul Perez View
18-0023 GATE Petroleum Comapany Patricia Carson View
18-0096 HOMENERGY Services, Inc Dan Reilly View
12-0054 DuPont Global Logistics Mr. Kevin M. Greene View
07-0019 Hy Yield Bromine Inc. Mr. Byver Daniell View
11-0032 RSLP, TASC Inc. Ms. Lisa Taylor View
13-0180 Mr. Tom Alexander View
12-0055 J. J. Keller & Associates, Inc. Mr. Tom Ziebell Sr. View
14-0178 South Carolina State Transport Police First Sergeant Dean Dill View
15-0120 Daniels Training Services Daniel Stoehr View
01-0082R MN DOT Office of Motor Carriers Mr. Michael Ritchie View
16-0020 Nebraska State Patrol Sgt. Brad Wagner View
12-0059 Mr. William Briner View
09-0171 Carus Corporation Mr. Chithambarathanu Pillai View
04-0059 Professional Emergency Resource Services Mr. Rich Heylmun View
03-0047 Halliburton Energy Services Mr. Johnny Cathey View
05-0069 Autoliv ASP, Inc. Mr. Dave Madsen View
14-0228 URS Corporation Mr. Andrew Romach View