This study was performed to estimate total dust concentrations and particle size distribution of wood dust in the furniture and sawmill industries.
To compare total wood dust concentrations, two samplers recommended by the American Conference of Governmental Industrial Hygienists and by the National Institute for Occupational Safety and Health were used.
Concentration data were analyzed by paired-t tests using the SAS program and two parameters of the particle size distributions were determined by histogram.
The results were as follows:
1. Particle size distributions showed a unimodal pattern in cutting and a bimodal in sanding operations. Mass median aerodynamic diameters(MMAD) were 17.35 ㎛ in cutting, and 1.39 ㎛ for small mode and 18.89 ㎛ for large mode in sanding operations. The proportions of particle size larger than 9.8 ㎛ estimated by the impactor were 61.16 % in cutting and 62.33 % in sanding operations, respectively.
2. The average personal total dust concentrations measured by IPM sampler were 17.12 ㎎/㎥ (GSD=1.45) from indoor samples, 2.97 ㎎/㎥(GSD=1.90) from outdoor samples in cutting, and 8.01 ㎎/㎥(GSD=1.58) from sanding operation. And those of by 37 ㎜ closed-face cassette were 9.12 ㎎/㎥(GSD=1.46), 1.06 ㎎/㎥(GSD=1.99) from cutting, and 3.32 ㎎/㎥ (GSD=2.16) from sanding operations.
3. The average area total dust concentrations measured by IPM sampler were 1.88 ㎎/㎥ (GSD=2.04) from indoor cutting, 4.76 ㎎/㎥ (GSD=2.83) from indoor sanding operations. And those of by 37㎜ closed-face cassette were 0.49 ㎎/㎥(GSD=2.34) from cutting, and 1.32 ㎎/㎥(GSD=3.03) from sanding operations.
4. The ratio of personal total dust concentrations measured by 37 ㎜ closed-face cassette to those by IPM sampler were 35.7 %, 53.3 % from cutting, and 41.4 % from sanding operations.
5. The ratio of area fatal dust concentrations measured by 37 ㎜ closed-face cassette to those by IPM sampler were 26.1 % from cutting, and 27.7 % from sanding operations.
6. A statistically significant difference of total dust concentrations between the 37 ㎜ closed-face cassette and the IPM sampler was found.
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