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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 #15-0031R ([Mr. Joe Connelly])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Joe Connelly

Location State: MD Country: US

View the Interpretation Document

Response text:

November 14, 2016

Mr. Joe Connelly
Specialty Transportation and Regulatory Services
P.O. Box 231
Elkton, MD 21922

Reference No. 15-0031R

Dear Mr. Connelly:

This is a revised response to your February 5, 2015, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). The Hazardous Materials Working Group of the Rail Safety Advisory Committee (RSAC) seeks to clarify the requirements for use of tank cars, among other requirements in Part 174. At a recent meeting of the working group, members discussed our response in Reference No. 15-0031 and expressed their belief that § 178.2(c)(1)(i)(B) did not apply to specification tank cars. After further consideration of our response in Reference No. 15-0031, we have determined that the reference to § 178.2(c)(1)(i)(B) closure instruction requirements is not appropriate for tank cars built to a specification in Part 179. Therefore, Reference No. 15-0031 has been superseded by this revised letter.

Specifically, you asked whether under § 173.31(d)(1), tank car bottom outlet valve caps must be removed and manway covers opened when an external visual inspection is performed prior to a tank car being offered for transportation.

The HMR do not explicitly state that bottom outlet valve caps must be removed to inspect the valve or manway covers opened to inspect the gasket of the covers. However, the HMR contain both minimum inspection requirements for a pre-trip inspection and for a performance standard. The minimum inspection requirements provided in § 173.31(d)(1)(ii) require that the piping, valves, fittings, and gaskets must be visually inspected for corrosion, damage, or any other condition that make a tank car unsafe for transportation. The performance standard is found in § 173.31(d)(2) and requires closures to be designed and closed so that under conditions normally incident to transportation there will be no identifiable release of hazardous material. See also § 173.24.

Specific to bottom outlet valves, on October 16, 2009, Federal Railroad Administration (FRA) issued Safety Advisory 2009-02 addressing the inspection of tank car bottom outlet valves and assemblies [74 FR 53321]. FRA specifically noted that although the then-current version of the HMR did not include explicit language requiring the removal of bottom outlet caps during the loading process, the performance standard of § 173.24 required that packages be "designed, constructed, maintained, filled...[and the] contents so limited, and closed, so that under conditions normally incident to transportation...there will be no...release of hazardous materials to the environment." Accordingly, in order to ensure compliance with this standard, FRA recommended in the advisory that bottom outlet caps be removed during the tank car loading process. If the cap is not removed, there is no way to determine whether the valve is in a condition safe for transportation because an internal defect in the valve may go undetected. In other words, if the bottom outlet cap is not removed, there is no way to ensure the tank car complies with the performance standard of either §§ 173.31(d)(2) or 173.24.

Similarly, without opening a hinged and bolted manway and observing the condition of the manway's gasket, there is no way an offeror can reasonably perform a visual inspection of the gasket to meet the minimum inspection requirement of § 173.31(d)(1)(ii) or know that the gasket meets the performance requirements of either §§ 173.31(d)(2) or 173.24. This rationale applies generally to other tank car fittings designed to be opened/removed for the purposes of loading or unloading and serve as primary or secondary closures (including, for example, plugs or caps on top valves, etc.). In order to ensure compliance with these requirements, an offeror must remove the bottom outlet cap and open the manway cover and inspect the condition of the gasket, regardless of whether the offeror used the fitting during a particular loading/unloading event.

Compliance with the performance standards of §§ 173.24 and 173.31(d)(2) and the minimum inspection requirements of § 173.31(d)(1)(ii) is aided by the establishment of specific rejection criteria against which the external visual inspections are to be performed (e.g., inspections for corrosion, damage, or any other conditions that make a tank car unsafe for transportation). We expect that inspection procedures take into account the information required in § 173.24(f)(2). This information should include gasket type, gasket dimensions, fastener specification, and other information relevant to the gasket's expected performance. Additionally, the inspection procedures should include specific rejection criteria that define the condemnable extent corrosion, the type and magnitude of damage (e.g., cracks, dents, scores, etc.), or a clear definition of other conditions identified by an offeror that makes a tank car unsafe for transportation.

I hope this information is helpful and apologize for any inconvenience this may have caused. If you have any more questions, please do not hesitate to contact this office.



Dirk Der Kinderen
Chief, Standards Development
Standards and Rulemaking Division

178.2(c)(1)(i)(B), 179, 173.31(d)(1), 173.24, 173.31(d)(1)(ii), 173.31(d)(2), 173.24(f)(2)

Regulation Sections

Section Subject
173.24 General requirements for packagings and packages
173.31 Use of tank cars