شینہائی دھماکہ پروف
A mixture of acetylene and oxygen, if it ignites and causes a standard gas cylinder to explode, results in certain fatality within a ten-meter radius. Apart from the risk of being hit by cylinder shrapnel, the immediate negative pressure and the blast wave from the explosion are powerful enough to be deadly.
I personally consider a distance of up to 20 meters from the explosion to be fatal. This scenario is exceedingly perilous.