Industry falls short of requiring comprehensive inspection or effective facility upgrades.
American Petroleum Institute (API) Recommended Practice (RP) 939-C: Guidelines for Avoiding
Sulfidation (Sulfidic) Corrosion Failures in Oil Refineries is the primary industry guidance
document on ways to monitor and control sulfidation corrosion. It states that carbon steel piping
can contain components with low silicon concentrations, and these components can corrode at a
faster rate than adjacent piping components. However, API RP 939-C does not specifically
require users to perform 100 percent component inspection or recommend that facilities upgrade
high-risk carbon steel piping circuits to steel alloys that are more resistant to sulfidation
corrosion.