This paper examines conditions that generates shock waves in a gas explosion through experiment. The result shows that the presence of barrier and thin film, which is similar to air door and stopping in underground coal mines, is very important for the generation of shock waves in a gas explosion. When there are physical barriers, the speed of transmission would be very fast and shock waves will result in the process; when the film is destroyed in gas explosion, shock waves will also appear which would result in an increase in explosion power. Therefore, in order to weaken the gas explosion and prevent the generation of shock waves, the number of barriers should be reduced, and the air door and stopping in tunnels should be strengthened in coal mines. The result of research is very important to prevent gas explosion and decrease the power of such explosions
