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United States Department of Transportation United States Department of Transportation

Railworthiness Directive for Railroad Tank Cars Equipped With Certain McKenzie Valve & Machining LLC Valves

Document Series
Directive Type
Directive Number
Railworthiness Directive, Notice No. 1
Subject Freight Operations, Hazardous Materials, Motive Power and Equipment
Railworthiness Directive; Hazerdous Materials; Valve; Tank Cars
This Directive requires railroad tank car owners to replace unapproved valves currently installed in some tank cars. The valves in question are UNNR ball valves manufactured and sold by McKenzie Valve & Machining LLC (McKenzie). Recent FRA investigations revealed that the valves were not approved for use on railroad tank cars. Additionally, the 3 inch ball valve, when not properly configured, is leading to tank cars leaking small quantities of hazardous materials.
Download image2015-03-13-102143.pdf
Last updated: Friday, March 13, 2015
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