A major aspect of pipeline safety is a sound, comprehensive compliance program, conducted by Regional Offices. To allocate its compliance resources in a manner to maximize the impact on safety, PHMSA uses a computer-based tool, known as the pipeline inspection priority program (PIPP), which ranks pipeline units on system characteristics, filed reports, and accident data. PIPP increases productivity by targeting inspections based on risk.

PHMSA investigates major pipeline accidents to determine whether violations of regulations occurred, whether revisions or additions to the regulations are needed and to ascertaining the cause of an accident. The objectives of a PHMSA investigation are to ensure future integrity of the pipeline and develop a sound basis for any enforcement actions taken.