Most inlets or outlets of tanks and reactors are linked vessels consisting of the tank or reactor itself and pipelines. In this study, a series of experiments was conducted to study the double-suppression effect of a multi-layer wire-mesh structure on methane-air mixture explosions in a spherical vessel connected to pipelines. The double-suppression effect was analyzed using explosion-suppression structures with different number of layers and meshes, and in particular, the effect was compared with the suppression of single-wire mesh. The results show that the explosion suppression effect primarily depends on both the number of layers and number of meshes. The number of layers plays a positive role in suppression when enough layers are used, and the number of meshes also has a significant effect on explosion suppression. It appears that the position of the wire mesh only has a slight effect on explosion suppression. The results provide a fundamental basis for actual explosion protection designs. (C) 2016 Elsevier Ltd. All rights reserved.