title: Comments on a recent protection factor study.
authors.forename: Thomas
authors.initials: T
authors.lastname: Nelson
mesh_terms: D000395:Air Pollutants, Occupational / Q000302:isolation & purification*; D004391:Dust; D005374:Filtration / Q000295:instrumentation / Q000592:standards; D006801:Humans; D019570:Inhalation Exposure / Q000517:prevention & control* / Q000592:standards*; D016273:Occupational Exposure / Q000517:prevention & control* / Q000592:standards*; D010316:Particle Size; D013172:Spores, Fungal / Q000302:isolation & purification
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust