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Section §171.7: Reference material

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 171.7 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
23-0015 UralKali Trading Marcel Cisneros View
21-0053 National Fireworks Association Steve Houser View
20-0081 Stablex US ecology Pierre-Olivier Gagné View
19-0136 National Propane Gas Association Sarah Reboli View
18-0155 Canal Terminology Company Cindy Van Duyne View
18-0151 Austin Powder Company Darrell A. Martin View
18-0135 Pyromanager Co. Ltd Robert Foti View
18-0024 Versum Materials Richard Schuyler View
18-0058 Breeze Executive, Ltd. George Tasick View
17-0120 Mihama Corporation View
15-0146 MGA Research Corporation Mr. Michael Greiner View
15-0203 FIBA Technologies, Inc. Mr. Christopher Adams View
11-0272 Safetech Mr. Robert Holley View
15-0207 Department of Army Mr. Marco Boasso View
09-0222 FIBA Technologies, Inc. Mr. Christopher R. Adams View
00-0078 Administrators International Ms. Kelly D. Enright View
12-0267 Allied Universal Corporation Ms. Robin Bolte View
02-0339 Occupational Safety and Health Administration Mike Marshall View
16-0064 OR-CAL Inc. Ms. Brooke Baker View
08-0082 Hydro-Test Products, Inc. Mr. Tom Sauta View
14-0153 Deitrich Engineering Mr. David Deitrich View
16-0178 ICL Americans Mr. Gregory Phillips View
11-0238 NitroxFox LLC. Mr. John Fox View
12-0114 Ford Motor Company Mr. Grant Haves View
16-0095 Jamestown Container Corporation Mr. Brian Storms View
12-0082 Silberline Manufacturing Co., Inc. Mr. Tom Shober View
12-0084 DOD Explosive Safety Board Mr. Brent E. Knoblett View
06-0147 Mr. Patrick F. Reilly  View
13-0242 Mr. Joseph E. Connelly View
10-0100 Wilhelmsen Ships Service Mr. Dave Finlay View
05-0207 The Fertilizer Institute Ms. Pamela D. Guffain View
15-0001 FIBA Technologies, Inc Mr. Christopher Adams View
14-0191 Daniels Training Services Mr. Daniel Stoehr View