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United States Department of Transportation United States Department of Transportation

Notice to Pipeline Operators: Exercise of Enforcement Discretion - API Specification 5L

Wednesday, May 1, 2019

On May 1, 2019, PHMSA issued a notice to pipeline operators that it does not intend to take any enforcement action relating to the requirements of American Petroleum Institute's (API) Specification 5L (Spec 5L) “Specification for Line Pipe” 45th edition, provided that API's new standard:  API Specification 5L, “Specification for Line Pipe,” 46th edition (April 2018, effective May 1, 2019), is used in its place.  The new edition includes slightly more stringent pipe end-straightness tolerance requirements and clarifications on how to define and measure end-squareness.  After May 1, 2019, the effective date of the 46th edition, API will require pipeline manufacturers with a license to use the API Monogram to manufacture and certify the line pipe to the 46th edition as part of their license with API. 

The federal pipeline safety regulations incorporate by reference numerous standards relating to the design, construction, operation, and maintenance of natural gas and hazardous liquid pipelines in parts 192 and 195.  PHMSA currently incorporates by reference the 45th edition of API Spec 5L in 49 CFR parts 192 and 195.  API Spec 5L is the primary manufacturing specification for seamless and welded steel pipe for use in both gas and hazardous liquid pipeline transportation systems.  The specification includes requirements for pipe material, manufacturing, quality control and testing, inspection, and pipe marking. 

This exercise of enforcement discretion is necessary to allow API licensed manufacturers to utilize the new standard before the May 1, 2019, effective date of the 46th edition. 

For more information, see the related documents section to the right of this page.