Objective

To set out the common European risk classification scheme (ERCS) for the determination of the safety risk of an occurrence.

Summary

The ERCS addresses the safety risk of an occurrence and not its actual outcome. The assessment must determine the worst likely accident outcome that the occurrence might have led to, and how close to that outcome it was.

The ERCS is based on a matrix composed of two variables:

• severity - the worst likely outcome that would have resulted if the occurrence had escalated into an accident;
• probability - the likelihood of the occurrence to escalate into that outcome.

The identification of the severity of the potential accident outcome is a two step process:

• determination of the most likely type of accident (the so called "key risk area");
• determination of the potential loss of life category based on aircraft size and proximity to populated or high-risk areas.

The key risk areas are: