respirator

1. A device to assist breathing.Examples: "Any N95 respirator is designed to filter out 95 percent of particles 0.3 microns or larger."; "The painters in the paint booth were wearing the kind of respirators with dual filter canisters."; "Similarly, a few studies have suggested that high-quality respirators can trap 95 percent of nanoparticles. But "whether 95 percent efficiency is good enough or not is still open to discussion," said Hung Min Chein of the Industrial Technology Research Institute in Chutung, Taiwan, who is studying the issue."