title: What is the recommended frequency and content of respirator user medical evaluations?
mesh_terms: D000328:Adult; D006304:Health Status; D006801:Humans; D008875:Middle Aged; D009314:National Institute for Occupational Safety and Health, U.S.; D009787:Occupational Medicine / Q000592:standards*; D012134:Respiratory Protective Devices; D014481:United States