Risk precontrol continuum and risk gradient control in underground coal mining

Underground coal mining is recognized all over the world as one of the riskiest industrial operations. To improve the safety management model in underground coal mines from passive management to active management, the risk precontrol continuum and risk gradient control in underground coal mining are proposed in this paper. The risk precontrol continuum is a continuous process in which three risk state correspond to three management models. Specifically, the stable safety state corresponds to the hazard management model whose management objectives are hazards; the unstable safety state corresponds to the defect management model whose management objectives are hidden dangers; and the emergency accidents state corresponds to the emergency management model whose management objectives are emergencies. These three management models exist simultaneously, and each management model plays a role in precontrol to eliminate or reduce certain risks. The management level of these three management models determines the risk precontrol level and risk level of a coal mining enterprise. Moreover, the three management models are not isolated or fragmented but are linked and form the risk precontrol continuum together. The risk precontrol level and management initiative rise continuously from emergency management model to defect management model to hazard management model. Finally, the idea of risk gradient control is proposed based on the risk precontrol continuum, which includes three gradients from high to low, namely, hazard control, hidden danger control, and emergency control. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.