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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #16-0001 ([Patriot Tank Lines Inc.] [Mark Mietz])

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

Interpretation Response Details

Response Publish Date:

Company Name: Patriot Tank Lines Inc.

Individual Name: Mark Mietz

Location State: NY Country: US

View the Interpretation Document

Response text:

June 3,  2016

Mark Mietz
Patriot Tank Lines Inc.
2737 Erie Drive
Weedsport, NY 13166

Ref. No. 16-0001

Dear Mr. Mietz:

This responds to your December 22, 2015 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to marking inlets and outlets on DOT Specification MC331 cargo tanks.  Specifically, you ask whether the marking provided in § 178.337-9(c) is required on the inlet and outlet equipment or on the cargo tank wall.  You also ask whether there is a size requirement for the marking and whether it needs to be stamped or embossed.

In accordance with § 178.337-9(c), except for gauging devices, thermometer wells, and pressure relief valves, each cargo tank inlet and outlet on a DOT Specification MC331 cargo tank must be marked “liquid” or “vapor” to designate whether it communicates with liquid or vapor when the cargo tank is filled to the maximum filling density.  The required markings must be on the inlet and outlet equipment itself and in close proximity to its respective make/break connection point, rather than on the cargo tank wall.  Furthermore, there is no minimum size requirement and no requirement for the markings to be stamped or embossed.  However, we recommend the marking be of a size and manner that is readily visible and durable such that it withstands the wear and tear of transport conditions.

I trust this satisfies your inquiry.  Please contact us if we can be of further assistance.

Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

Regulation Sections

Section Subject
178.337-9 Pressure relief devices, piping, valves, hoses, and fittings