METHODOLOGY FOR MATRIX RISK ASSESSMENT

The risk assessment function according to ISO 31010 is v(p,u), where p ∈0÷1 is an expert assessment of probability, u = 1,2,3,4,5 is an expert assessment of the consequences of the risk occurrence. In this matrix the assessment function
v(p,u) = p.u

The four sectors of risk prevention priorities are set by expertly defined values of k, so that when p.u k the evaluation corresponds to a given priority and when p.u > k, it doesn’t.

p - probability assesment priority k ≤
high 0,99 0,99 1,98 2,97 3,96 4,95 2,4 < high ≤ 4,95
medium-high 0,79 0,79 1,58 2,37 3,16 3,95
medium 0,59 0,59 1,18 1,77 2,36 2,95
medium-low 0,39 0,39 0,78 1,17 1,56 1,95 1,2 < medium ≤ 2,4
low 0,19 0,19 0,38 0,57 0,76 0,95 0,4 < low ≤ 1,2


u - consequences
1 2 3 4 5 0 < dispensable ≤ 0,4
minimal
light
medium
heavy
catastrophic