Critical control effectiveness monitoring

Landslide in opencast mine

In mining, there is a plethora of risks, many of which, should they eventuate as incidents, can result in injury or loss of life and equipment, and so organisations set up critical controls to prevent them.  Critical control effectiveness monitoring (CCEM) is an additional, and vital layer of defence. It enforces constant vigilance of how effective your critical controls are.

In an open cast mine, an ever-present danger is wall failure. At Anglo American’s Dawson mine in Australia, the side wall of a pit collapsed, and buried a truck and excavator. Paul de Kock, Director: Product Strategy at IsoMetrix, explains how an incident like this might have been prevented, “Critical control effectiveness monitoring (CCEM) is by nature preventative. You identify the risk and then analyse the effectiveness of the critical controls that you have put in place. If any of those critical controls fail, it is likely that an event will materialise.”

“During a risk assessment, you look at the cause of the risk. In this case, there was a failure in the rock strata. The contributing factors were geotechnical issues, mining activities that progressively removed support from the pit wall, and a failure in communication,” explains Paul.

Rock falls are always a risk in open cast mining. To minimise this risk, you need to understand what controls should be put in place and what you should be monitoring so that you know that you are warned before a potential failure becomes actual. Says Paul, “Some of the critical controls in this example are that they had a radar monitoring movement in the rock wall. These give you an early warning. However, they need to be constantly monitored to ensure they are functioning properly and that warnings are clearly communicated across the correct channels.”

In the case of Dawson Mine, there was a failure to manage critical controls over the long term. CCEM puts an extra layer of protection in place. CCEM does not replace day-to-day checks and monitoring processes routinely undertaken by supervisors. What it does provide is an additional higher-level assurance process to verify and ensure the ongoing effectiveness of critical controls for the identified unwanted risks.

One of the requirements for verifying the effectiveness of critical controls is ensuring that signs of a potential unwanted event are communicated along the necessary channels and that these have been acted on. “You should also be physically monitoring the top of the pit wall for cracks and build a rock wall barrier so that if the wall fails the barrier is between the vehicles and people working there,“ explains Paul. “In the case of this example, all of those controls failed, and an incident occurred.”

“The shift in thinking now is to look at the controls. This is a more effective way of addressing these risk assessments,” says Paul. These processes need to be monitored systematically and effectively, and information about the status of actions needs to be visible so that it is immediately apparent if the unwanted risk is likely to occur, giving enough time to evacuate people and equipment if necessary.

While this example is specific to mining, critical control effectiveness monitoring is applicable for all risks. “If your critical controls fail, it raises the likelihood of that risk becoming an event. If your critical controls are not in place, you will have people in harm’s way when the event happens,” stresses Paul. It is imperative to recognise these risks and act timeously and appropriately to prevent damage to property and loss of life. This means looking at, and reviewing on an ongoing basis, the effectiveness of your critical controls for all risks within your environment.

You do not have to wait for the worst case scenario to expose your organisation’s most vulnerable risk areas. A critical control effective monitoring process requires the following:

  • A thorough baseline assessment of risks across the organisation
  • Identifying ‘Unwanted events” such as those that could lead to multiple fatalities
  • Identifying the controls required for the management of these unwanted events with comprehensive risk assessment, typically using a “bow-tie analysis”.


Prevention is always cheaper than cure.  As the discipline of risk of risk management matures, there is an increasing focus on leading rather than lagging indicators, and critical control management enforces this approach.