Risk Assessment Matrix

A risk assessment matrix plots likelihood against consequence and produces a rating. It is genuinely useful for one thing and routinely used for another.

It is good at communication. Two people rating the same risk differently have to explain why, and that conversation is where most of the value sits.

It is poor as a calculation. The scales are ordinal, so a rating of four is not twice a rating of two, and multiplying them does not produce a meaningful number. Ratings also cluster in the middle, because extreme positions invite questions.

Use it to prioritise conversation and to force ownership onto a named person. Do not use it to rank risks precisely, or to justify a decision on the arithmetic alone.

Safe Work Australia covers risk assessment under work health and safety duties. This is general information rather than legal advice, and obligations vary by state and territory.

See Sentrient’s risk management system and GRC system.