... seal which is suitable for different face.2.MF18type gas mask Specifications: Service life, min Penetration Leakage coefficient ... , cyanogens chloride, arsine, phosgene, chloropicrin, bromomethane, lewisite gas, mustard gas, sarin, vx gas, toxic smoke, and fume, benzene, hydrogen phosphide, chlorine ... on this occasion, bowing down and taking a deep breath, the sweat would release form the exhaust clack. ...