A type of hydrogen-induced failure produced when hydrogen atoms enter low-strength steels that have macroscopic defects, such as laminations.

The defects in the steel (void spaces) provide places for hydrogen atoms to combine, forming gaseous molecular hydrogen (H₂) that can build enough pressure to produce blistering.

Hydrogen blistering is a problem mainly in sour environments. Frequently, it does not cause a brittle failure, but it can produce rupture or leakages.