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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 #PI-20-0011

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

Interpretation Response Details

Response Publish Date:

Company Name: Southern California Gas Company

Individual Name: Mr. Travis Sera

Location State: CA Country: US

View the Interpretation Document

Response text:

Mr. Travis Sera
Director of Integrity Management
Southern California Gas Company
555 W. Fifth Street
Los Angeles, CA 90013

Dear Mr. Sera:

In a letter to the Pipeline and Hazardous Materials Safety Administration (PHMSA), dated May 4, 2020, you requested an interpretation of 49 Code of Federal Regulations (CFR) Part 192. Specifically, you requested an interpretation of § 192.113 as it relates to the longitudinal joint factor (E) for steel used under § 192.105 to determine a natural gas pipeline maximum allowable operating pressure (MAOP).

You stated that San Diego Gas & Electric and Southern California Gas Company are aware of a March 10, 2020, submission to PHMSA by the Public Advocates Office for an interpretation of the Longitudinal Joint Factor for Line 1600. You stated that your request relates to the Line 1600, a 50-mile San Diego Gas & Electric gas transmission pipeline located in San Diego County, California. Finally, you stated that "through this request, SDG&E and SoCalGas seek to confirm that the operator's possession of company Standard Specifications for Line Pipe and historical work order documents which both state a requirement that 16-inch pipe meet the American Petroleum Institute (API) 5L/5LX Pipe Specification, and thus affirmatively rules out pipe classes with LJFs less than 1.0 because API 5L does not allow furnace butt welds on pipe over 4-inches or any "other" pipe class with an LJF less than 1.0, are sufficient to establish a Longitudinal Joint Factor of 1.0."

In support of your request, you provided background information and documents. You ask whether a longitudinal joint factor of 1.0 is properly determined based on historical records under § 192.113, if the historical records for the 50-mile 16-inch diameter Line 1600 pipeline meets Specification API 5L or 5LX, when such Specification required a pipe class with a longitudinal joint factor of 1.0.

As stated in our May 7, 2020 letter to the Public Advocates Office, the longitudinal joint factor to be used in the design formula in § 192.105 is determined in accordance with the table listed for § 192.113. Methods for determining the pipe joint factor can be based upon different factors, such as whether the pipe diameter(s), wall thickness(es), yield strength, and manufacturing period are applicable for that seam type. Also, the seam type can be determined based upon inspections (excavations or pipe removals) of the pipe in accordance with the testing parameters (spacing for tests and whether destructive or nondestructive) in §§ 192.107, 192.109, 192.619(a)(4), or 192.624 as applicable. Further, the table included in § 192.113 states that if the type of longitudinal joint cannot be determined, the joint factor to be used must not exceed that designated for "Other." For "Other" pipe over 4 inches (102 millimeters), the longitudinal joint factor E is 0.8.

Your request, although couched in terms of seeking an interpretation on the application of a specific regulation to Line 1600, is more properly viewed as a request for a declaratory judgment from PHMSA to resolve a factual dispute between you and the California Advocates Office as it relates to the longitudinal seam type for Line 1600. The information provided to us by the Advocates Office is that the longitudinal seam type is unknown, which requires a factor E of 0.8. The information provided by you, in contrast, purports to establish that the seam type is known and a factor E of 1.0 is appropriate under the regulation.

PHMSA provides written clarifications of the Federal pipeline safety regulations that reflect the agency's current application of the regulations to the specific facts presented by the person requesting the clarification. Interpretations are not generally applicable, do not create legally-enforceable rights or obligations, and are provided to help the specific requestor understand how to comply with the regulations. In this case, San Diego Gas & Electric and Southern California Gas Company are disputing the California Public Advocates Office's presented information and, therefore, are requesting that PHMSA resolve a factual issue. PHMSA is not in a position to validate one party's assertion of facts over the other. Accordingly, PHMSA suggests that both parties resolve the factual dispute through physical inspection of the pipeline in question, or through other appropriate means.

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


John A. Gale
Director, Office of Standards
and Rulemaking

Regulation Sections

Section Subject
192.113 Longitudinal joint factor (E) for steel pipe