Worst case aerosol testing parameters. I. Sodium chloride and dioctyl phthalate aerosol filter efficiency as a function of particle size and flow rate

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

DOI:https://doi.org/10.1080/15298668991374615· OSTI ID:5883274

Stevens, G A; Moyer, E S

The efficiency of filter media is dependent on the characteristics of the challenge aerosol and the filter's construction. Challenge aerosol parameters, such as particle size, density, shape, electrical charge, and flow rate, are influential in determining the filter's efficiency. In this regard, a so-called ''worst case'' set of conditions has been proposed for testing respirator filter efficiency in order to ensure wearer protection. Data collected on various types of filters (dust and mist; dust, fume, and mist; paint, lacquer, and enamel mist; and high efficiency) challenged with a worst case-type sodium chloride (NaCl) and dioctyl phthalate (DOP) aerosol are presented. The particle size of maximum penetration varies as a function of filter type and was less than 0.25-micron count mean diameter (CMD) in all cases. The count efficiency for high efficiency filters was greater than 99.97% at worst case testing conditions, but the worst case count efficiencies for dust and mist; dust, fume and mist; and paint, lacquer and enamel mist filters were not nearly as efficient as existing test methods indicate. Also, as the test flow rate is increased, the count efficiency decreases. Thus, respirator filters were found to conform to the prediction of single-fiber filtration theory.

• Research Organization: National Institute for Occupational Safety and Health, Morgantown, WV (USA)
• OSTI ID: 5883274
• 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
CARBOXYLIC ACIDS
CHLORIDES
CHLORINE COMPOUNDS
COATINGS
COLLOIDS
DICARBOXYLIC ACIDS
DISPERSIONS
DUSTS
EFFICIENCY
ENVIRONMENTAL EXPOSURE
EQUIPMENT
FILTERS
FILTRATION
FLOW RATE
HALIDES
HALOGEN COMPOUNDS
LACQUERS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PAINTS
PARTICLE SIZE
PERFORMANCE TESTING
PHTHALIC ACID
POLLUTION CONTROL EQUIPMENT
RESPIRATORS
SEPARATION PROCESSES
SIZE
SODIUM CHLORIDES
SODIUM COMPOUNDS
SOLS
TESTING