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Section §173.199: Category B infectious substances

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.

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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 173.199 on the ECFR website

Interpretation Responses

Ref ID Date Company Name Individual Name Response Document
23-0067 Andelyn Biosciences Dave Curl View
23-0087 North Carolina Department of Health and Human Services Kristi Jenkins View
17-0063 Morton Plant Mease Health Care, Inc. Ms. Beth Schelle View
14-0060 Safe-T- Pak, Inc. Mr. David Creighton View
07-0018 Saf-T-Pak Gail Ryckis-Kite View
09-0102 Inmark, Inc. Mr. Junius Johnson View
03-0070 Mildred Mitchell Bateman Hospital Ms. Gail Kelly, MT (ASCP) View
02-0264 First Filtration International Co., Ltd. Alastair Hayton-Williams View
10-0188 American Veterinary Medical Association Ms. Kristi Henderson View
03-0161 ARUP Laboratories Mr. Paul H. Brinton View
06-0269 Inmark, Inc. Mr. Junius "Jay" Johnson  View
15-0154 Inmark Packaging, Inc. Mr. Jay Johnson View
08-0158 Toppenish Community Hospital Carolyn Arms, MT(ASCP) View
11-0023 BioStorage Technologies Ms. Darcy Britt View
15-0152 DiSorb Systems, Inc Mr. Ted McLaughlin View
12-0051 United Parcel Service Mr. Samuel Elkind View
12-0028 Waste and Compliance Management, Inc. Mr. Eric Smith View
11-0227 Inmark Mr. Jay Johnson View
07-0087 The Council on Safe Transportation of Hazardous Articles, Inc. Mr. John V. Currie View
07-0088 SAIC-Frederick, Inc. Ms. Shawn K. Brown  View
11-0112 Midstate Air Freight and Logistics, Inc., DBA Callahan Air Expediters Mr. Jeremy K. Nantz View
09-0065 ACM Global Central Laboratory Ms. Lisa Fotheringham View
04-0043 Ms. Cynthia Harrell Ms. Cynthia Harrell View
08-0276 PAML Ms. Marguerite Busch View
15-0092 Inmark Packaging Mr. Jay Johnson View
09-0011 Association of Clinical Research Professionals Mr. David Vulcano View
16-0044 Hall, Render, Killiam, Heath & Lyman, PC Ms. Amy Berenbaum Goodman View
14-00132 Quest Diagnostics Mr. Nicholas Pagerly View