2022-05 – Dust Caps on 400-Series Low-Pressure Cargo Tanks

Background

Certified inspectors have cited violations for a missing dust cap at the end of the discharge line connection area on 400- series low-pressure cargo tanks.

§178.345-11(c) states that any loading/unloading outlet extending beyond an internal self-closing stop-valve, or beyond the inner-most external stop-valve, which is part of a self-closing system, must be fitted with another stop-valve or other leak-tight closure at the end of such connection.

The §178.345-11(c) definition of stop-valve means a valve that stops the flow of the lading (cargo).

The discharge pipe dust/safety cap is not a stop-valve or other leak-tight closure at the end of the discharge pipe. The dust/safety cap is a convenience to the driver/carrier as its intention is to keep debris and other contaminates out of the discharge line connection area.

Guidance

U.S. - Dust caps used to prevent debris from entering the connection area are optional devices and do not meet the definition of stop-valve or other leak-tight closure. A missing dust cap does not constitute a violation of §178.345-11(c) and should not be cited as a violation.

Canada - CSA Standard B621 requires compliance with the requirements of sections 7.4 and 7.7. Dust caps used to prevent debris from entering the connection area are optional devices and do not meet any definition of the Standard.

A missing dust cap is not a violation of section 7.4 or 7.7 of the CSA Standard B621 and should not be considered as a non-compliant means of containment under Part V of the TDG Regulations.