Worst case aerosol testing parameters: II. Efficiency dependence of commercial respirator filters on humidity pretreatment

Journal Article · Mon May 01 04:00:00 EDT 1989 · Am. Ind. Hyg. Assoc. J.; (United States)

DOI:https://doi.org/10.1080/15298668991374624· OSTI ID:5883216

Moyer, E S; Stevens, G A

Previous studies have shown that relative humidity has a degrading effect on the performance of commercially available particulate air-purifying respirator filters. That degradation results from a reduction of charge within the filter. This study was done to evaluate the time-dependent effects of relative humidity pretreatment and the reduction of charge on filter penetration against a most penetrating, ''worst case'' aerosol challenge. Filters of the dust and mist; dust, fume, and mist; paint, lacquer, and enamel mist; and high efficiency types were tested after being pretreated in an environment of 38 degrees C and 85% relative humidity for periods up to 42 days. After various intervals of pretreatment (1, 7, 14, 28, and 42 days), the filters were tested against neutralized worst-case sodium chloride (NaCl) and dioctyl phthalate (DOP) aerosols for percent penetration. The results showed a drop in filter efficiency of approximately 2%-6% depending on preconditioning time, except for the high efficiency filters tested which showed no detectable change.

• Research Organization: National Institute for Occupational Safety and Health, Morgantown, WV (USA)
• OSTI ID: 5883216
• Journal Information: Am. Ind. Hyg. Assoc. J.; (United States), Journal Name: Am. Ind. Hyg. Assoc. J.; (United States) Vol. 50:5; ISSN AIHAA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOLS
AIR FILTERS
ALKALI METAL COMPOUNDS
CHLORIDES
CHLORINE COMPOUNDS
COATINGS
COLLOIDS
DISPERSIONS
DUSTS
EFFICIENCY
ENVIRONMENTAL EXPOSURE
EQUIPMENT
FILTERS
FILTRATION
HALIDES
HALOGEN COMPOUNDS
HUMIDITY
LACQUERS
PAINTS
PERFORMANCE TESTING
POLLUTION CONTROL EQUIPMENT
RESPIRATORS
SEPARATION PROCESSES
SODIUM CHLORIDES
SODIUM COMPOUNDS
SOLS
TESTING
TIME DEPENDENCE