Glossary · PA Workers' Comp

Hazard Group

A PCRB classification grouping similar-risk class codes together for actuarial credibility in calculating experience modifiers.

Definition

The PCRB assigns each class code to a hazard group — a classification that groups together class codes with similar risk profiles and expected injury rates. Hazard groups (typically labeled A through G or similar designations) are used in experience rating calculations to provide actuarial credibility.

How PCRB Hazard Groups Affect Your Experience Modifier Calculation

Hazard groups ensure that when comparing an employer's actual claims to "expected" claims, the comparison is made against similar-risk businesses. A roofer's claims are compared against other roofers (high-hazard group), not against clerical workers.

The hazard group is a property of the class code, not the employer. All employers in Code 551 (Roofing) are in the same hazard group regardless of their specific location or history.