... 40>40min,Type 60>60min poison gas and smoke protecting,fireproof,hot-radiation protecting,sealing Description This kind ... 40>40min,Type 60>60min poison gas and smoke protecting,fireproof,hot-radiation protecting,good sealing property,suitable ... anid(HCN),poison smoke and fog. 3. Mist permeability coefficient <5%; 4. Inhalation resistance <800Pa,Exhalation resistance<300Pa. Fire Escape Mask/fire mask