• Probability of occurrence
    Severity of occurrence
    Negligible Minor Major Hazardous Catastrophic
    Extremely improbable 1 1 1 1 2
    Extremely remote 1 1 1 2 3
    Remote 1 1 2 2 3
    Occasional 1 2 2 3 3
    Probable 1 2 3 3 3

    Risk index Significance Description
    3 High Unacceptable
    2 Medium Tolerable based on risk mitigation
    1 Low Acceptable, monitoring action required