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Interpretation Response #PI-18-0021

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

Interpretation Response Details

Response Publish Date:

Company Name: IHI E&C International Corporation

Individual Name: Mr. Don Boudreaux

Location State: TX Country: US

View the Interpretation Document

Response text:

Mr. Don Boudreaux
Project Director
IHI E&C International Corporation
15377 Memorial Drive, Suite 300
Houston, TX 77079

Dear Mr. Boudreaux:

In a letter to the Pipeline and Hazardous Materials Safety Administration (PHMSA) dated August 17, 2018, you requested a reconsideration of PHMSA's June 18, 2018, response to your initial March 7, 2018, interpretation request concerning marking with die-stamping of a 24-inch diameter, stainless-steel pipeline with 1/4-inch wall thickness to be used as a liquefied natural gas (LNG) vapor line. You stated the process to mark the pipe is done under controlled automated process where low-stress stamping dies are used to emboss markings into flattened stainless steel from coils prior to going through the pipe forming process. In addition, you stated that in the manufacturing process, the pipes are heat treated which relieve any residual stresses created by the embossing and significantly reduces the potential for crack initiation. You believe the National Fire Protection Association (NFPA) 59A-2001 requirement in Section 6.3.5 does not apply to your marking processes because the requirement is for field pipe marking.

At a meeting with PHMSA on October 25, 2018, you provided additional information. You supported your reconsideration request with the following: (1) the structure of Chapter 6 of NFPA 59A-2001, the previous version of Part 193 regulations, evaluation of Section 6.3.5 of NFPA 59A-2001 by IHI's independent expert, and the industry recognizing a difference between stamping and embossing in support of the restriction in use of field die-stamping; (2) the 1/4-inch wall thickness restriction is understood by IHI, IHI's independent expert, the impacted suppliers and manufacturers to be a nominal thickness; (3) there is no risk of fatigue failure due to the die-stamping; and (4) PHMSA's interpretation would force a significant change in industry practices. Based on the information you provided, you asked PHMSA to reconsider its June 18, 2018, interpretation to your original request.

Section 6.3.5 of NFPA 59A-2001, Pipe Marking, clearly states that materials less than 1/4-inch wall thickness shall not be die-stamped for flammable liquids and flammable gases with service temperatures below -20° F. The NFPA standard does not specifically state nominal thickness. Moreover, PHMSA rejects IHI's suggestion that nominal wall thickness should be "implied" in NFPA 59A. NFPA 59A does not use or apply the term or concept of nominal wall thickness. Therefore, PHMSA cannot read the term into the standard. In this case, IHI is not able to reference specific language in the Part 193 regulations to support its reconsideration effort, and much of its argument is based on previous standards language. For example, IHI argued historically, the standards prohibited marking "in the field" and that although the word "field" was removed from the current language, it should remain implied as to application. This is contrary to the rules of statutory construction. By removing the word "field" from the standard, rather than assuming "field" still applies to the standard, PHMSA interprets the standard to be applied as written - and therefore not being limited to marking in the field only.

After examining your latest information, including your in-person presentation, PHMSA has determined that its June 18, 2018 interpretation should remain as issued. PHMSA's interpretations are based on current applications of the regulations to specific facts presented by the person requesting the clarification. In this case, requirements that are no longer in the current PHMSA regulations are not applicable.

If we can be of further assistance, please contact Tewabe Asebe at 202-366-5523.


Alan K. Mayberry
Associate Administrator
for Pipeline Safety

Regulation Sections

Section Subject