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: Insignificant
 

2: Minor
 

3: Moderate
 

4: Major
 

5: Catastrophic
 

(a)
Almost certain

Expected to occur in most circumstances

Significant risk Significant risk Severe risk Severe risk Severe risk

(b)
Likely

Will probably occur in most circumstances

Moderate risk Significant risk Significant risk Severe risk Severe risk

(c)
Moderate

Given time, likely to occur

Low risk Moderate risk Significant risk Severe risk Severe risk

(d)
Unlikely

More likely not to occur under normal conditions

Low risk Low risk Moderate risk Significant risk Significant risk

(e)
Rare

May only occur in exceptional circumstances

Low risk Low risk Moderate risk Significant risk Significant risk

Severity of consequences

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.

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.