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

Interpretation Response #18-0116

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

Interpretation Response Details

Response Publish Date:

Company Name: Columbiana Boiler Company, LLC

Individual Name: Tina Cousins

Location State: OH Country: US

View the Interpretation Document

Response text:

Tina Cousins
Product Manager
Columbiana Boiler Company, LLC
200 West Railroad Street
Columbiana, OH 44408

Reference No. 18-0116

Dear Ms. Cousins:

This letter is in response to your August 16, 2018, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the authorized use of tank cars for the transportation of certain poisonous by inhalation (PIH) materials. Specifically, you ask whether "UN1067, Dinitrogen tetroxide, inhibited, 2.3," may be shipped in a Department of Transportation (DOT) 110 multi-unit tank car tank under the provisions in § 173.314(c). You reference a final rule published on January 13, 2009 (74 FR 1787; HM-246) in which the preamble states, "Multi-unit tank car tanks and forged-welded tank car tanks (e.g., DOT 106, DOT 109, and DOT 110) may continue to be used as authorized."

The answer is yes. "UN1067, Dinitrogen tetroxide, inhibited, 2.3," may be shipped in a DOT 110 multi-unit tank car tank under the provisions in § 173.314(c). Note 11 was added to the § 173.314(c) table to clarify that for tank cars built prior to March 16, 2009, and used to transport PIH materials, the then-current class of authorized tank cars may continue to be used, provided the tank cars were approved by the AAR Tank Car Committee for transportation of the specified material. DOT 110 multi‑unit tank car tanks were authorized for dinitrogen tetroxide at that time. Multi-unit tank car tanks and forged‑welded tank car tanks (e.g., DOT 106, DOT 109, and DOT 110) were not affected by the 2009 final rule and may continue to be used as authorized.

Thank you for bringing this typographical error to our attention. We intend to correct it in a future rulemaking action.

I hope this information is helpful. Please contact us if we can be of further assistance.

Sincerely,

T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

Regulation Sections

Section Subject
173.314 Compressed gases in tank cars and multi-unit tank cars