What is API 5L equivalent to?

API 5L is a standard for seamless and welded steel pipes for pipeline transportation systems in the petroleum and natural gas industries.

It doesn't have a single direct equivalent, but in terms of similar standards, there are some international and regional standards that cover related aspects of pipe manufacturing and quality. For example, the EN 10208 standard (in Europe) also deals with steel pipes for the transportation of fluids including in the energy sector and has some overlapping requirements in terms of material properties, dimensions, and testing methods as API 5L, though there are differences in specific details such as the range of grades and exact testing procedures.