Evaluation of the andersen viable impactor for single stage sampling.
Jones-W; Morring-K; Morey-P; Sorenson-W
Am Ind Hyg Assoc J 1985 May; 46(5):294-298
The usefulness of a modified six stage sampler in measuring concentrations of viable airborne microorganisms was investigated. The advantages of the six stage sampler over standard six stage samplers and currently used methods were determined. All the samplers were operated at a flow rate of 1 cubic foot per minute. The pumps were calibrated before each survey and calibrations were checked upon return from the field. Rose-Bengal-Streptomycin growth media was used to estimate viable airborne concentrations of fungi. All the samplers were operated side by side in a poultry confinement house. The petri plates, after sampling, were stored in an inverted position in an incubator at 30 degrees-C and counted on days 2, 3, or 4 after sampling. The highest count was used to calculate colony forming units per cubic meter of sampled air. The standard six stage sampling method gave consistently lower values compared to the modified six stage method. The precision of the modified method was about 8 percent; the standard sampling had greater than twice the background values at 19 percent. The modified sampler was superior to the standard method over a wide range of airborne fungal concentrations between 10 and 3,000 colony forming units per cubic meter of sampled air. The modified method had the advantage of being simpler than any of the current methods. The authors conclude that the modified sampler is simple and of high precision for measuring total concentrations of airborne fungi.
NIOSH-Author; Quantitative-analysis; Hygiene; Work-environment; Sampling; Industrial-environment; Analytical-methods; Occupational-exposure; Pulmonary-congestion; Industrial-exposures; Analytical-models
American Industrial Hygiene Association Journal