How to conduct a risk assessment
Step 2 in conducting a safety assessment enables mine operators to understand the level of risk posed by the identified mining hazards.
What is a risk assessment
A risk assessment is the process and associated documentation used to determine the risk of a major mining hazard (MMH) event taking place at a prescribed mine.
Risk is calculated by considering the likelihood of an MMH event occurring along with the severity of its consequences.
Use a risk matrix
Risk matrices are a convenient way of expressing the likelihood and severity of MMH events.
It is important that stakeholders agree on the definitions of likelihood and severity, such as the ones provided in the example risk matrix below. Typically, each box in the risk matrix is colour-coded so that, for example, severe risks are red and low risks are green.
Once the risk matrix is prepared, add each of the hazards that could cause an MMH event by placing them in the appropriate box based on their likelihood and severity.
This exercise must be completed with appropriate stakeholders, including HSRs, relevant experts and affected employees.
| Severity of consequences | |||||
|---|---|---|---|---|---|
|
Likelihood of the event |
1: |
2: |
3: |
4: |
5: |
|
(a) Expected to occur in most circumstances |
Significant risk |
Significant risk |
Severe risk |
Severe risk |
Severe risk |
|
(b) Will probably occur in most circumstances |
Moderate risk |
Significant risk |
Significant risk |
Severe risk |
Severe risk |
|
(c) Given time, likely to occur |
Low risk |
Moderate risk |
Significant risk |
Severe risk |
Severe risk |
|
(d) More likely not to occur under normal conditions |
Low risk |
Low risk |
Moderate risk |
Significant risk |
Significant risk |
|
(e) May only occur in exceptional circumstances |
Low risk |
Low risk |
Moderate risk |
Significant risk |
Significant risk |
Severity of consequences
Any injury or disease that needs first aid treatment only.
Any injury or disease that is likely to result in a person being incapacitated from normal activity for a continuous period of up to 7 days.
Any injury or disease that is likely to result in a person being incapacitated from normal activity for a continuous period of 7 or more days.
A fatality or total and permanent disability.
Multiple fatalities.
Prioritise the risks
Once you have entered into your risk matrix each hazard, or combination of hazards, which could lead to an MMH event you can easily prioritise its risk and allocate appropriate effort/resources to addressing it.
The section below shows how you might assign actions to hazards/MMH events based on their level of risk.
Stop activity and rectify immediately.
Rectify with urgency.
Actively look for opportunities to further reduce risk.
Consider if anything simple can be done to reduce the risk. If not, manage as part of a continuous improvement program.
What to document during your risk assessment
Potential severity of harm caused by the MMH event
- Record any assumptions and comments regarding this decision.
- Remember to consider any harm to any person.
- It is common for there to be several different severities from a single MMH event.
Likelihood of the MMH event occurring and resulting in harm
- Record any assumptions and comments regarding this decision.
- Remember to consider the likelihood of any harm to any person.
Effectiveness of any existing controls
- Remember that controls are rarely perfect as you consider how well each control would work in each applicable scenario.
Consider all levels of severity
When carrying out a risk assessment it is important to think about the varying levels of impact a single event may have.
For example, in a worst case scenario an MMH event could result in multiple fatalities. However, the same event could also result in less severe outcomes, such as lost time injuries, medical treatment injuries or first aid injuries.
It is due to this range of severities that the Regulations require all identified MMH events to be assessed for any harm to any person – not just focused on the worst case scenario of multiple fatalities.