... ~50C; 20~95%R.H. 11standard:Electrochemistry CO alarm only use to detect CO gas.CO gas is ... to be safty,we suggest you to install CO alarm in kitchen,wash room,dinning room,bedroom,,garage ... etc.When the unit detector gas leakage,it will alarm with 85db sound,meantime the red indicator light. ... function of low voltage warning and testing.If it alarm when you press the testing button for several seconds ...