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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 #16-0176 ([SGS Petroleum Service Corporation] [Mr. Glenn Gillaspia])

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

Interpretation Response Details

Response Publish Date:

Company Name: SGS Petroleum Service Corporation

Individual Name: Mr. Glenn Gillaspia

Location State: TX Country: US

View the Interpretation Document

Response text:

April 5, 2017

Glenn Gillaspia
Compliance Manager
SGS Petroleum Service Corporation
5055 Preston Avenue
Pasadena, TX 77505

Reference No. 16-0176

Dear Mr. Gillaspia:

This letter is in response to your October 20, 2016, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to securement of rail tank car closures. Specifically, you ask whether chains are required on caps or plugs used to secure openings on product and vapor valves located inside the top housing on DOT Specification 111 tank cars.

The answer depends on the design as it was approved by the Association of American Railroads (AAR) Tank Car Committee. As prescribed in § 179.200-17(a)(1), bottom outlet reducers, closures, and their attachments are required to be secured to the car by 3/8-inch or 1/4-inch chain under certain conditions. The HMR do not contain a similar provision for top fittings, such as liquid and vapor valves on DOT Specification 111 tank cars. However, §§ 179.3 and 179.200-16 require the tank car design and top loading and unloading devices to be approved by the AAR Tank Car Committee. Thus, a chain is required on a liquid or vapor line closure, such as a pipe plug, if the tank car design as approved by the AAR Tank Car Committee includes a chain attached to the closure.

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



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

179.200-17(a)(1), 179.3, 179.200-16

Regulation Sections

Section Subject
179.200-16 Gauging devices, top loading and unloading devices, venting and air inlet devices
179.200-17 Bottom outlets
179.3 Procedure for securing approval