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Interpretation Response #09-0209 ([INDSPEC Chemical Corporation] [Ms. Vicki H. Weightman])

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

Interpretation Response Details

Response Publish Date:

Company Name: INDSPEC Chemical Corporation

Individual Name: Ms. Vicki H. Weightman

Location State: PA Country: US

View the Interpretation Document

Response text:

April 21, 2010




Ms. Vicki H. Weightman

Manager, Technical Services and Regulatory Affairs

INDSPEC Chemical Corporation

1010 William Pitt Way

Pittsburgh, PA 15238

Ref. No. 09-0209

Dear Ms. Weightman:

This responds to your September 2, 2009 letter requesting clarification of requirements for loading tank cars with hazardous materials under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether the tank car loading operation must be attended.

Section 173.31 provides general requirements for transporting hazardous materials in tank cars, including tank car loading and unloading requirements. Additional requirements for loading and handling tank cars are in § 174.55. Section 174.67 establishes requirements for transloading tank cars - that is, for transferring hazardous materials from one tank car to another tank car or from a tank car to a cargo tank motor vehicle or vice versa. Transloading operations must be attended in accordance with § 174.67(i); however, the HMR do not include specific requirements for attending rail tank car loading operations.

We have initiated a rulemaking to consider whether additional measures are necessary to reduce the risks associated with loading and unloading of bulk packagings containing hazardous materials, including rail tank cars. We plan to publish a notice of proposed rulemaking in 2010.

I hope this answers your inquiry. If you need further assistance, do not hesitate to contact our office.


Charles E. Betts

Chief, Standards Development

Office of Hazardous Materials Standards

173.31, 174.55, 174.67

Regulation Sections

Section Subject
174.31 Requirements for the operation of high-hazard flammable trains
174.55 General requirements
174.67 Tank car unloading