Authors: Joughin, WC


Cite As:
Joughin, WC 2008, 'A Preliminary Model for Quantifying the Risk of Rockfalls and Evaluating the Benefits of Safety Spending', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), SHIRMS 2008: Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium, Australian Centre for Geomechanics, Perth, pp. 589-604,

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Safety spending in the mining industry is often viewed as a necessary but expensive overhead cost. This mindset places safety and productivity in direct opposition to each other, while improved safety practices could actually lead to better productivity. Alternatively, from a pure safety perspective, the perception also exists that more is better in terms of safety spending, while the additional spending may not necessarily lead to a significant reduction in risk. In order to evaluate the real benefits of safety spending in mitigating rockfalls and their consequences a risk model is being developed as part of an ongoing SIMRAC research programme. A preliminary model has been developed and is presented in this paper. The model will enable the quantification of the likelihood of occurrence rockfalls under various conditions with different support systems. It will also allow the likelihood of occurrence of the various direct and indirect consequences of rockfalls to be determined. The effect of various monitoring and mitigating strategies can also be evaluated through the model. If the costs associated with these consequences are known, then the model can be used to determine the expected cost of rockfalls. The overall cost of a safety strategy can then be determined as the sum of the cost of implementing and maintaining the strategy and the expected cost of rockfalls with the strategy implemented. It will provide a method for designing according to tolerable levels of safety risk.

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