Particulate filtering facepiece respirator
https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html
Healthcare > Pulmonary disease
Controlling silica dust
Tighter, Controversial Silica Rules Aimed At Saving Workers’ Lungs
March 24, 2016
http://www.npr.org/sections/health-shots/2016/03/24/471585412/tighter-controversial-silica-rules-aimed-at-saving-workers-lungs
About 2.3 million people in the U. S. are exposed to fine grains of silica on the job; inhaling the dust is one of the oldest known workplace hazards. Silica, which is basically sand, scars the lungs, causing diseases like silicosis and cancer.
