Covers the use of in-line inspection systems for onshore and offshore gas and hazardous liquid pipelines. It includes, but is not limited to, tethered or free flowing systems for detecting metal loss, cracks, mechanical damage, pipeline geometrics, and pipeline location or mapping. The document applies to both existing and developing technologies. This document is an umbrell document that provides performance-based requirements for in-line inspection systems, including procedures, personnel, equipment, and associated software.