Establishing an occupational health & safety management system based on ISO 45001

APPENDIX D: A 6X6 RISK MATRIX FOR SEVERITY AND LIKELIHOOD

The following paragraphs describe a 6x6 risk ranking matrix of likelihood and severity. The risk evaluation is based on the classic definition of risk where:

Risk = Probability of the Event combined with its Potential Severity.

This methodology requires risks classified as significant to be addressed first. As the performance of an organisation improves, risks with a lower-risk ranking should also be considered.

Table D1: A 6x6 Risk Matrix

The severity scale is described in Table D2.

Table D2: Severity Scale

1	First aid case.
2	Minor medical intervention or rest for a few hours, or restricted ...