<p>To reduce the deflagration hazard effects of methane/air mixtures, in this work the synergistic effects of ammonium dihydrogen phosphate-modified dry water (MAP-DW)-C₃HF₇ inhibitors on the explosion parameters of methane were experimentally investigated. Moreover, the synergistic thermal-chain inhibition mechanism of the compound inhibitor was revealed by kinetics analysis. The experimental results show that with the increase in the compound inhibitor, the P_max and (dP/dt) _max of the methane/air decrease, while t_b and t_c extend. The addition of MAP-DW eliminates the explosion-promoting effect of C₃HF₇ on the fuel-lean and stoichiometric methane. The chemical kinetics calculation results show that the adiabatic flame temperature and laminar flame velocity of methane within various equivalence ratios decrease under the influence of the compound inhibitors. The thermal inhibition effects of MAP-DW-C₃HF₇ suppressant were attributed to the heat absorption during their pyrolysis process. Meanwhile, the intermediates containing F and P atoms, generated from the pyrolysis processes, contribute most to the chemical suppression effect. They combined with the key free radicals, promoting the termination of methane explosion. The obtained results are helpful for promoting the safely utilization of methane.</p>