Technology schemes of upgrading of coal mine safety monitoring and control system clearly stated that monitoring and control system should have functions of predicting and warning of gas emission, but it did not explain how to analyze early warning results. In view of this problem, status and characteristics of gas warning of monitoring and control system were analyzed. It was pointed out that the gas warning involved in current safety monitoring and control system mainly includes two aspects: gas emission warning and gas outburst warning. Comprehensive evaluation method of gas warning results using early warning recognition rate and false alarm rate was proposed. For gas emission warning, it was pointed out that taking absolute amount of gas emission and change of gas fluctuations to make the necessary trade-offs for early warning indicators is one of the important factors that must be considered in the warning of gas emission. In analysis of warning results of gas outburst, drill cuttings index was used to classify risk of gas outburst into three states: safety, threat and danger, and the threat state was set according to 80% of the dangerous state threshold.
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