... .ZH15 self-rescuer is a protection device for human respiratory system, it apply to mine well, fire disaster, anaerobic environment, poisonous gases environment, chemical ... +H2O →2KOH+1.5O2+heat 2KOH+CO2 →K2CO3+H2O+heatStructure\ ZH15 HOT Self-rescuer under mine,protable respirator,Isolated from the type of chemical oxygen self-rescuer