Risk Assessment Impact Calculation

Risk impact is calculated by multiplying Probability x Severity.

High risk equals 16 to 25

Medium risk equals 9 to 15

Low risk equals 1 to 8

Probability Severity
5. Almost certain 5. Fatality
4. Probable 4. Major injury, resulting in disability
3. Possible 3. Injury requires doctor’s or hospital attendance
2. Possible (under unfortunate circumstances) 2. Minor injury, 1st aid required
1. Rare 1. Minor injury, 1st aid not required
Impact rating


risk assessment matrix