This review examines existing knowledge on the genesis and flame acceleration of explosions from methane-air mixtures. Explosion phases including deflagration and detonation and the transition from deflagration to detonation have been discussed. The influence of various obstacles and geometries on explosions in an underground mine and duct have been examined. The discussion, presented here, leads the readers to understand the considerations which must be accounted for in order to obviate and/or mitigate any accidental explosion originating from methane-air systems. (C) 2016 Elsevier Ltd. All rights reserved.