Sampling methods to assess worker exposure to grain dust.
Occupational Pulmonary Disease: Focus on Grain Dust and Health. Dosman JA, Cotton DJ, eds. New York: Academic Press, 1980 Jan; :537-543
Monitoring methods for the assessment of worker exposure to grain dust are reviewed. To measure harmful and potentially harmful occupational exposures from grain dusts, accurate monitoring methods are required. Personal monitoring systems are the preferred approach because they collect representative breathing zone samples. Direct reading instruments are useful for identifying potentially dangerous situations immediately. Dust samples, whether personal or environmental, can be collected in membrane filters or in liquid filled impingers. The sample is returned to the laboratory for analysis by gravimetric, microscopic or chemical analysis. A portable direct reading instrument usually sizes particles based on aerodynamic parameters. If the vapor pressure of solid or liquid samples is high, a bubbler or solid sorbent may be needed to increase sampling efficiency. Any analytical method must be suited for routine use. Accuracy must be better than about 25 percent for 95 percent of the samples taken over a range from 0.5 to 2.0 times the desired concentration. At least 75 percent of the sample must be desorbed. Over the same time ranges the desired concentration biases between the true concentration and that determined by an independent method must be no greater than about 10 percent. For time weighted concentrations the minimum sample time is 1 hour. The mean of six samples immediately analyzed must agree with the mean of six samples from the same time stored for 7 days. The author concludes that accurate and precise sampling and analysis allow the comparison of epidemiological and toxicological data without questioning the validity of the environmental measurement.
Health-hazards; Sampling-methods; Analytical-methods; Dust-exposure; Industrial-exposures; Breathing-zone; Environmental-factors; Monitoring-systems; Workplace-studies; Exposure-levels; Occupational-exposure
Occupational Pulmonary Disease: Focus on Grain Dust and Health