| 摘要 |
A dust respirator consists of three-layer filtering semi-mask with the nasal clamp. The facial layer of filtering semi-mask is made of foamy polyurethane, the middle layer – of filtering material entrapping the fine disperse particles. The internal layer is made of the thin airproof film with inbuilt lobe of the breathing valves connected to the spreader. The respirator also contains the hood and the unit of breathing-out valve with the protective screen. When the lobes of the breathing-in valves contact mechanically with the saddles of the valves, the saddles are also sealed in the openings of the airproof film. |
