HSE DIRECTIVE 11 SAFE JOB ANALYSIS - BP

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ATTACHMENT 5: RISK MATRIX
Assessment of hazards – probability and consequence
In some cases it may be appropriate for the SJA group to use
a risk matrix in the assessment of a hazard, i.e. assessing
the probability of an undesirable incident occurring, and its
consequences. A risk evaluation of this kind may help clarify
the need and priority of measures to reduce the risk or its
consequences.
The evaluation method is a rough qualitative approach, and
high-risk hazards may well be subjected to a more detailed
evaluation later on.
Using the risk matrix
A risk matrix is used to assess/estimate risk by plotting the
probability of an undesirable incident along one axis and the
degree of consequences along the other axis. This must be
done for each subtask, cf. the SJA form. If the combination of
probability and consequence (cf. the matrix) reaches Medium
or High, measures will be needed.
Probability
Consequence Low Medium High
Low L L M
Medium L M H
High M H H
Degree of consequence/severity
High Fatal, serious injury, >1 Day Away From Work Case,
considerable damage to equipment or supplies,
considerable pollution or loss of production
Medium Day Away From Work Case or minor injury, minor
damage to equipment or supplies, minor pollution
or loss of production
Low No injuries, minor/slight damage to equipment or
supplies, minor/slight pollution.
Probability:
High Probably, may happen several times
Medium Possible, may happen now and then
Low Not very realistic/likely, but conceivable