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Interpretation Response #08-0303 ([OSI] [Ms. Carolynn Buenger                                     ])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: OSI

Individual Name: Ms. Carolynn Buenger                                     

Location State: TX Country: US

View the Interpretation Document

Response text:

January 16, 2008





Ms. Carolynn Buenger                                     


1212 N. Velasco

Angleton, Texas  77515


Ref. No.: 08-0303


Dear Ms. Buenger:


This responds to your December 9, 2008 request for clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) as they apply to the transportation of materials that are poisonous by inhalation (PIH materials).  Specifically, you suggest that there is an error in § 172.400a(d), which excepts PIH materials from labeling or placarding requirements under certain conditions.


As currently drafted, § 172.400a(d) excepts PIH materials transported in a closed transport vehicle or freight container from labeling or placarding requirements under the conditions set forth in § 171.23(b)(11).  You are correct that this section reference is incorrect. The correct reference is § 171.23(b)(10)(iv), which establishes criteria for the use in the United States of labels and placards authorized under the International Maritime Dangerous Goods Code and Canada"s Transport of Dangerous Goods regulations. We will correct this reference in a future rulemaking.


I hope this answers your inquiry.






Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards


172.400, 171.23

Regulation Sections

Section Subject
171.23 Requirements for specific materials and packagings transported under the ICAO Technical Instructions, IMDG Code, Transport Canada TDG Regulations, or the IAEA Regulations
172.400 General labeling requirements