Performance of N-, R- and P-series respirator filters against diesel exhaust.
Berardinelli-S; Sandy-M; Martin-S Jr.; Moyer-E
American Industrial Hygiene Conference and Exposition, June 2-7, 2001, New Orleans, Louisiana. Fairfax, VA: American Industrial Hygiene Association, 2001 Jun; :70
The National Institute for Occupational Safety and Health (NlOSH) certifies nonpowered air-purifying particulate respirator filters according to 42 CFR 84. Air-purifying respirator filters are categorized as N-, R- or P- depending on their resistance to degradation. N-series filters are not resistant to oil, and R- and P-series filters are recommended for use in all work environments. There are three levels of efficiency within each filter series, 95, 99, and 100 (99.97) percent. Previous NlOSH studies have demonstrated filter media efficiency reduction resulting from constant and intermittent aerosol exposures in the laboratory. This study is part of a larger study to test for the degradation of respirator filters in the field. N-, R- and P-series filters were exposed to varying concentrations of diesel exhaust in an underground mine. Testing was conducted at the NIOSH Lake Lynn Laboratory experimental mine facility near FairChance, PA. The ventilation characteristics of the mine were altered to provide suitable exposure. The source was a diesel-powered portable welder, which would have applications in both the mining and construction industries. Filters were tested in quadruplicate at a flowrate of approximately 50 L/min. Filter load was determined gravimetrically with parallel sampling conducted during diesel exposures. All filters were loaded at varying concentrations up to about 50 mg of diesel particulate matter and then tested for penetration using 42 CFR 84 certification test aerosols. In all of the filters tested, penetration values increased from that of the controls, but especially the N-series filters with electrostatic media which would not met the penetration criteria of 42 CFR 84. These data demonstrate that a diesel-powered welder can significantly affect the filter efficiency of N -series respirators.
Particulates; Respirators; Respiratory-equipment; Respiratory-protection; Filters; Air-purifying-respirators; Exposure-levels; Laboratories; Diesel-exhausts; Exhaust-gases; Underground-mining; Construction; Construction-equipment
American Industrial Hygiene Conference and Exposition, June 2-7, 2001, New Orleans, Louisiana