Methane explosion threats the safety in mining, gas recovery and the related downstream industry. The present study examined the suppression effect of KHCO3 (K) modified montmorillonite (K/MMT) inhibitor on reducing the hazard of methane/air mixtures explosion. The characteristic indices of explosion containing the maximum pressure (P-max), the maximum rate of pressure rise ((dP/dt)(max)), the time of pressure peak arriving (t(max)), were experimentally obtained in a standard 20 L explosion device. The hazard mitigating effect of each modified inhibitor was evaluated. which also elucidated the inhibition mechanism based on the characteristic parameters of K/MMT. Results showed that the K/MMT demonstrates better suppression effect than monomer inhibitor and the maximum decrease of P-m(ax), (34.9 %) and (dP/dt)(max) (94.4 %) occurs when 45 wt% KHCO3 are loaded (45 wt%-K/MMT). When 45 wt%-K/MMT is used, 0.125 g/L is the optimal concentration to decrease K-G to a minimum of 0.849 MPa m/s. This work presents an efficient modified inhibitor by using innovative technology, which is applied to mitigate or prevent disaster. The technology also provides theoretical support and technical guidance for the future development of inhibitors. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.