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Section §173.166: Safety devices

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 173.166 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
19-0055 Dangerous Goods Transport Consulting Inc. Frits Wybenga View
18-0113 Autoliv ASP, Inc. Dave Madsen View
18-0035 COSTHA Don Bossow View
00-0006 Shipmate, Inc. Mr. Steven Charles Hunt View
00-0007 Shipmate, Inc. Mr. Steven Charles Hunt View
13-0215 Savethesituation Ms. Eva Glimsche View
13-0225 iSi Automotive Austria GmbH Mr. Jürgen Tröscher M.A. View
12-0133 Autoliv Ogden Technical Center Mr. Dave Madsen View
02-0204 D&G Consulting, Inc Glen K. Wanczyk View
12-0107 North American Automotive Hazardous Materials Action Committee Mr. Dave Madsen View
10-0201 Ford Motor Company Mr. Grant Haves View
00-0272 TRW Automotive Mr. Matt Hatfield View
13-0189 JBE Enterprises Mr. Frank Hannah View
11-0043 International Vessel Operators Dangerous Goods Association Mr. John V. Currie View
16-0038 Lear Corporation-Guilford Mills Ms. Laura Jones View
13-0168 Sandler, Travis & Rosenberg, P.A. Mr. Mark Ludwikowski View
98-0374 Mitsubishi Motor Manufacturing of America Edwin C. Amsler View
14-0047 Sandler, Travis & Rosenberg, P.A. Mr. Mark Ludwikowski, Esq. View
05-0289 ShipMate, Inc. Mr. Steven Charles Hunt View
04-0214 D & G Consulting, Inc. Mr. Glen K. Wanczyk View
06-0263 Packaging Technology Center Mr. Thomas Schneider View
12-0133R Autoliv Ogden Technical Center Mr. Dave Madsen View
07-0047 Fluoro-Seal International Mr. Paul J. Crook View
09-0007 Mr. Joseph A. Taranovich American Honda Motor Company View