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Interpretation Response #03-0093 ([Riddick Engineering Corporation] [Mr. Chris J. Teas, PE ])

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

Interpretation Response Details

Response Publish Date:

Company Name: Riddick Engineering Corporation

Individual Name: Mr. Chris J. Teas, PE 

Location State: AR Country: US

View the Interpretation Document

Response text:

Jun 13, 2003

 

Mr. Chris J. Teas, PE                Ref. No.: 03-0093
Riddick Engineering Corporation
Consultants
2300 Cottondale Drive Suite 200
Little Rock, Arkansas 72202

Dear Mr. Teas:

This responds to your letter regarding requirements for an internal self-closing stop valve on a DOT 407 cargo tank under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you asked whether a "swing check valve" as shown in the enclosed diagram would be acceptable to meet the "internal self-closing stop valve" provisions in § 178.345-11 (b).

Each specification DOT 407 cargo tank must conform to the general design and construction requirements in § 178.345 in addition to the specific provisions contained in §178.347. Each cargo tank (e.g., DOT 407) loading/unloading outlet must be equipped with an internal self-closing stop valve or with an external self-closing stop valve located as close as practicable to the cargo tank wall.

An internal self-closing stop valve is a self-closing stop valve designed so that the self-stored energy source is located inside the cargo tank or cargo tank sump, or within the welded flange, and the valve seat is located within the cargo tank or within one inch of the external face of the welded flange or sump of the cargo tank. The regulations do not prohibit a design of the type, such as the "swing check
valve," shown in the enclosed diagram if it meets all of the requirements for an "internal self-closing stop valve," specified in § 178.345-11 (b). You did not provide sufficient information in your letter or a detailed drawing of the components of the "swing check valve" for us to determine if it complies with the requirements in §178.345-11(b).

If we can be of further assistance, please contact us.

Sincerely,

 

Delmer F. Billlings
Chief, Standards Division
Office of Hazardous Materials Standards

Regulation Sections