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Interpretation Response #06-0035 ([Supervac 2000, Inc.] [Ms. Nathalie Doyon])

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

Interpretation Response Details

Response Publish Date:

Company Name: Supervac 2000, Inc.

Individual Name: Ms. Nathalie Doyon

Country: CA

View the Interpretation Document

Response text:

Jul 11, 2006

Ms. Nathalie Doyon                Reference No.06-0035

Supervac 2000, Inc.

1043 Rue Renault

St-Jean-Chrysostome, Qc G6Z1B6

Dear Ms. Doyon:

This responds to your fax dated February 13, 2006 requesting clarification on tank outlets for cargo tank motor vehicles in § 178.345-11(b)(2) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask if a manual double action valve at the top of the tank meets the provisions of § 178.345-11(b)(2).

According to your fax and the additional diagram provided, your company manufactures vacuum equipment with a manual double action valve on the top of the tank. You want to use a manual double action valve on the top of the tank that is not connected to the emergency valve, and, does not close the top of the tank. You request confirmation on whether use of this manual double action valve would meet the provisions of § 178.345-11(b)(2).

Section 178.345-11(a) requires cargo tank outlets, closures and associated piping to be protected in accordance with § 178.345-8. In addition, §178-345-11(b)(1) provisions require each cargo tank loading/unloading outlet be equipped with an internal self-closing stop-valve, or alternatively, with an external stop-valve located as close as practicable to the cargo tank wall. Each loading/unloading outlet must be fitted with a self-closing system capable of closing all such outlets in an emergency within 30 seconds of actuation. During normal operations the outlets may be closed manually. Under § 178.345-11(b)(2), bottom loading outlets that discharge lading into the cargo lank through fixed internal piping above the maximum liquid level of the cargo tank need not be equipped with a self-closing system

It is the opinion of this Office that the manual double action valve depicted in the diagram you provided does not conform to § 178.345-11 because it is not connected to the emergency valve and does not close the top of the tank. Section 178.345-11(b)(2) does not apply to your scenario.

I hope this answers your inquiry.


Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
178.345-11 Tank outlets