Probably the most critical hazard related to using gas-powered instruments comes from gas vapors that may burn or explode and likewise give off harmful exhaust fumes. Earlier than refilling a gasoline-powered device tank, the person should shut down the engine and permit it to cool to stop the unintended ignition of hazardous vapors. When a gasoline-powered software is used inside a closed space, efficient ventilation, and/or correct respirators reminiscent of environment-supplying respirators should be utilized to keep away from respiration carbon monoxide. When utilizing pneumatic instruments, a security clip or retainer should be put in to forestall attachments corresponding to chisels on a chipping hammer from being ejected throughout instrument operation. If an air hose is greater than 1/2-inch (12.7 millimeters) in diameter, a security excess stream valve has to be put in on the supply of the air provide to scale back strain in case of hose failure.