Magazine article Occupational Hazards

Risk Assessment: Focusing on the Operator

Magazine article Occupational Hazards

Risk Assessment: Focusing on the Operator

Article excerpt

In Australia, the Liberty International Risk Services offices have been successfully using an unusual, perhaps even unique, approach to risk assessments. They call the technique "Workplace Risk Assessment and Control" (WRAC). It is a participative qualitative risk assessment focused on the worker rather than on the process.

In general, it is similar to HAZOP and the requirements of the OSHA process safety management standard, but with some twists. Jim Joy, a Canadian who emigrated to Australia, refined the technique from earlier systems safety approaches used in Canada and the U.S.

WRAC Phases

The method consists of many different steps, but essentially three main phases. The first is the scoping session. where the scope of the risk assessment is developed, the team selected and the risk levels of concern defined. The second phase is the risk assessment, in which the team performs a qualitative risk analysis within the scope defined in the first phase. The final phase is the client or management review, where corrective actions are evaluated based on their impact on reducing risk as defined by the team.

The WRAC technique is an approach that will be familiar to those in systems safety. The approach is, in part, based on the examination and control of releases of unwanted energy. The overall concept of unwanted energy release and hazards control came from work in the nuclear industry on "Management Oversight Risk Tree," or MORT, developed in the 1970s.

What is most interesting about the WRAC approach is the use of a relative risk ranking technique using a team approach. The team approach is also used to suggest control measures as well as define acceptable risk. Risk assessment is being used by an increasing number of safety and health professionals, and one that allows workers to help define acceptable risk should be of particular interest in team-based environments.

In the remainder of this article, I will quickly provide an overview of the WRAC methodology using a simple example of the replacement of a mechanical press with a newer and faster hydraulic press in a factory making small parts.

Scoping the Work

The first step in the process is the scoping phase. It could be done by a single individual with training in the WRAC approach (e.g., a health and safety professional), a management group or others familiar with the WRAC process. The scoping phase consists of identifying risks of concern to be evaluated. This is followed by defining the work objective, the risk ranking, acceptability of risk and expected outcomes from the study. Based on this work, a risk assessment team is established and a scoping document prepared.

For example, a scoping document might be prepared which involves the replacement of an old mechanical press with a new, faster hydraulic press. The scope document (typically a single-page form) might state the work objective as the assessment of potential risks involved with the installation and use of the new press. The scoping document would also identify the amount of time anticipated for the completion of the risk assessment (estimated in this scenario at two days), acceptable risks levels and the outcome expected of the WRAC process.

The expected outcome in this example would be a list of actions that could be taken to reduce risk in the operation of the new press (to include safe work practices). Acceptable risk is developed from a set of tables using a "five-by-five" risk ranking matrix. The risk ranking elements are shown below:


A - Common or repeating occurrence

B - Known to occur or has happened

C - Could occur

D - Not likely to occur

E - Practically impossible



1 - Fatality or permanent disability

2 - Serious lost time injury or illness

3 - Moderate lost time injury or illness

4 - Minor lost time injury or illness

5 - No lost time

Equipment, assets or production (note this listing could include environmental effects):

1 - More than $500K damage or equivalent cost for production delays

2 - $100K to $500K damage or equivalent cost for production delays

3 - $50K to $100K damage or equivalent cost for production delays

4 - $5K to $50K damage or equivalent costs for production delays

5 - Less that $5K damage or equivalent cost for production delays

The risk values are found in the table below by choosing the proper probability column (A-E) and then going across the consequence rows (1-5) in the left column. …

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