Combustible gas detector calibration certificate type not certified features a rugged ergonomic design that makes it comfortable to use gases detected are acetaldehyde ammonia benzene ethane ethanol ethylene hexane hydrogen hydrogen sulfide isobutane methane p-xylene propane toluene includes the battery maximum operating temperature 115 degrees F minimum operating temperature 32 degrees F ppm accuracy +/-10 ppm ppm detection range 0 to 6 400 ppm probe length 16 in.