Filtering facepiece respirators with an exhalation valve: measurements of filtration efficiency to evaluate their potential for source control. National Institute for Occupational Safety and Health, 2021, nro 2021-107. doi:10.26616/NIOSHPUB2021107Artikkelin verkkoversio.
Filtering facepiece respirators with an exhalation valve: measurements of filtration efficiency to evaluate their potential for source control. National Institute for Occupational Safety and Health, 2021, nro 2021-107. doi:10.26616/NIOSHPUB2021107Artikkelin verkkoversio.