Occupational Risk Assessment

Risk Assessment Matrices for Workplace Hazards: Design for Usability

“…Risk management today involves several processes, repeated periodically, to identify hazards, evaluate the associated risks, and assess various tactics for preventing and mitigating harm from those risks [ 2 , 3 , 4 ]. A tool used for assessing and evaluating risks is referred to in the OSH field as a risk table, risk grid, risk matrix, or (our preference) risk assessment matrix (RAM) [ 2 , 3 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ].…”

“…The cells inside the grid are used to indicate risk. Risk-assessment teams use RAMs as part of an organization-specific risk management process [ 2 , 3 , 5 , 7 , 8 , 11 ]. Although the details differ somewhat, a risk-management process involves: (1) identifying hazards and the associated risks, (2) determining tactics for reducing/mitigating each risk, also called risk treatment, (3) assessing the risks in terms of credible harmful consequences and likelihood of occurring, (4) evaluating each hazard-specific risk in terms of the organization’s tolerance for risk, (5) communicating with those affected, (6) implementing the approved risk-reduction tactics, and (7) following up by monitoring implementation and effectiveness.…”

“…For a specified hazard, the individuals participating in a risk assessment are expected to both foresee possible hazard scenarios and estimate how likely each may occur [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. These projections must then be put into the column and row categories of the applicable RAM.…”

“…Yellow cells are those separating green and red cells. For OSH, a hazard rated in the green band is generally considered tolerable or acceptable, and a hazard in the red band is typically considered highly undesirable or not tolerable [ 5 , 6 , 7 , 8 , 9 , 10 ]. While the decisions associated with red and green cells are often stated as clear-cut rules, the preferred practice is to consider these as indicators to assist with making decisions [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 24 ].…”

“…A risk assessment matrix provides an easily understood depiction of risk being based on the product of applicable values in the row (probability or likelihood) and column (severity). Although this approach has been a tradition in the field of system safety, the OSH community has, for various reasons, sought a less quantitative approach [ 5 , 7 , 8 , 9 , 10 , 11 , 15 , 19 , 20 ].…”