A holiday is a pinhole, void, or discontinuity in a pipeline’s protective coating that exposes bare steel to the surrounding environment — creating a site for corrosion initiation.

A holiday is a pinhole, void, or discontinuity in a pipeline’s protective coating that exposes bare steel to the surrounding environment — creating a site for corrosion initiation. The term originates from the concept of a “gap” or “break” in coverage, similar to a holiday from work.

Holidays can occur during coating application (manufacturing defects, contamination, insufficient thickness) or develop in service from mechanical damage, soil stress, thermal cycling, UV degradation, or chemical attack. Even microscopic holidays can initiate significant corrosion if cathodic protection is insufficient at that location.

Holiday detection methods include:
• High-voltage holiday detectors (jeep testing) — factory and field testing of new coatings.
• DCVG/ACVG surveys — aboveground detection of coating defects on buried pipelines.
• CIPS surveys — identifying CP anomalies indicating coating degradation.

EMPIT’s CMI technology detects holidays and coating defects on buried pipelines from the surface — and critically determines whether active corrosion is occurring at each defect location. This active/passive classification enables operators to focus remediation on holidays that pose real integrity threats.