title: Particle concentration in exhaled breath.
authors: H E
authors: HE
authors: Ayer
authors: K
authors: K
authors: Willeke
mesh_terms: D000336:Aerosols; D001944:Breath Tests / Q000379:methods*; D004781:Environmental Exposure; D006801:Humans; D011482:Protective Devices; D012134:Respiratory Protective Devices
chemical_list: D000336:Aerosols