Hydrogen-Induced Cracking (HIC) is a material degradation mechanism where atomic hydrogen diffuses into the pipeline steel matrix, accumulating at inclusions and laminations to form internal blisters and cracks.

Hydrogen-Induced Cracking (HIC) is a material degradation mechanism where atomic hydrogen diffuses into the pipeline steel matrix, accumulating at inclusions and laminations to form internal blisters and cracks. HIC is primarily associated with sour service environments containing hydrogen sulfide (H₂S), making it a critical concern for oil & gas pipelines.

HIC develops without external stress — distinguishing it from Stress Corrosion Cracking (SCC) and Sulfide Stress Cracking (SSC). Susceptibility depends on steel cleanliness, microstructure, hardness, and H₂S concentration. Materials conforming to NACE MR0175/ISO 15156 are specified to resist HIC in sour environments.

Detection methods include ultrasonic testing (UT) for internal crack mapping, hydrogen probe monitoring, and surface inspection for blister indicators. EMPIT’s CMI technology complements HIC management by detecting external corrosion and material anomalies that may coincide with hydrogen damage zones, supporting comprehensive pipeline integrity assessment.