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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #22-0094

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

Interpretation Response Details

Response Publish Date:

Company Name: AllTranstek, LLC

Individual Name: Larry Loman

Location State: IL Country: US

View the Interpretation Document

Response text:

January 26, 2023

Larry Loman
Director, Engineering
AllTranstek, LLC
1101 W. 31st Street, Suite 200
Downers Grove, IL 60515

Reference No. 22-0094

Dear Mr. Loman:

This letter is in response to your September 7, 2022, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to structural integrity inspections and testing for rubber-lined DOT 111A100W5 tank cars that were qualified for service by a Canadian tank car facility. In your email, you state that these tank cars were constructed with exterior heater coils that cover the tank shell butt welds and that fact complicates the ability to inspect and test the structural integrity of the tank shell butt welds in accordance with § 180.509(e)(1)(iii). You further state that it is your understanding that this is not required for rubber-lined tank cars with reinforced tank shell butt welds until such time the lining is removed in accordance with § 180.509(e)(3). You ask whether the heater coils that cover the tank shell butt welds would allow for the butt welds to be treated as reinforced tank shell butt welds, thereby only requiring inspection at the time of lining removal or application.

The answer is no, having heater coils that cover the tank shell butt welds would not constitute reinforced tank shell butt welds. However, this fact would not itself require the tank cars owner to cut the heater coils to allow for inspection and testing of the tank shell butt welds within two (2) feet of the bottom longitudinal centerline. As stated in § 180.509(e)(1)(iii), the tank shell butt welds must be tested unless the tank car owner can determine by analysis—e.g., finite element analysis, damage-tolerance analysis, or service reliability assessment—that the structure will not develop defects that reduce the design level of safety and reliability or fail within its operational life or prior to the next required inspection. Please note the tank car owner must also maintain all documentation used to make such determination at its principal place of business and make the data available to the Federal Railroad Administration or an authorized representative of the Department upon request.

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


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

180.509(e)(1)(iii), 180.509(e)(3)

Regulation Sections

Section Subject
180.509 Requirements for inspection and test of specification tank cars