... gas mask(Silica Gel mask) . 2.ISO9001,CEcertificate,GB2890-1995 3.supply sample. 4.Enlarging the field of ... , arsine, phosgene, chloropicrin, bromomethane, lewisite gas, mustard gas, sarin, vx gas, toxic smoke, and fume, benzene, hydrogen ... Usage maintenance and maintain4.1.The selection of gas mask 4.1.1. checking the ... .The procedure of wearing gas mask 4.2.1. adjusting the position of fillets 4.2 ...