USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation


Section §172.406: Placement of labels

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 172.406 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
21-0030 Wellmatics Joshua Howk View
20-0067 Linde Gas N.A., LLC Kevin Funk View
19-0013 Hunter Fan Company Tony Bacon View
16-0198 C&J Energy Services Ltd. Mr. George Doggett View
14-0109 VEGA Americas, Inc. Mr. John F. Birch View
08-0243 Lovelace Gas Service, Inc. Mr. Bill Lovelace View
15-0120 Daniels Training Services Daniel Stoehr View
16-0055 AZKO Nobel Services, Inc. Mr. Mark Connolly View
12-0249 Praxair Distribution, Inc. Mr. David B. Sonnermann View
10-0247 View
04-0069 NOVA Chemicals Corporation Mr. Kevin Duncan View
99-0235 Modern Safety Techniques Mr. Charles F. Martin, P.E. View
02-0207 Paul Reamy View
99-0093 Clariant Corporation Mr. Robert F. Rau View
12-0153 Autoliv ASP, Inc. Mr. Dave Madsen View
07-0157 FedEx Express Mr. Thomas J. Leech, III View
04-0102 Brenntag Stinnes Logistics Mr. A. B. Eargood View
12-0059 Mr. William Briner View
06-0245 Reagent Chemical & Research, Inc. Mr. Robert Dritschel View
11-0294 Sea-Land Chemical Co. Mr. Kerry McMahon View
11-0250 W.M. Barr & Company Mr. John Rhodes View
07-0104 Raytheon Technical Services Company Mr. James Traylor  View
13-0238 Veolia ES Technical Services LLC Mr. Richard Finnegan View
10-0160 Empire Airlines, Inc. Mr. Bradley J. Slater View
10-0088 Dyno Nobel, Inc. Mr. Mark Anderson View