Relationship between the Measurement Values of the Digitial Dust Indicator and Personal Dust Sampler / 예방의학회지

The digital dust indicator (Sibata P-5), one of the direct-reading instruments was evaluated for the respirable dust in the underground coal mine environments. As a reference, respirable dust was determined using three cyclones and/or impactors. All the tests were performed on aerosol in twenty underground coal mines. The coefficients of mass-relative concentration were 0.067+/-0.054 (Mean+/-Standard deviation) (range: 0.006-0.172). The relationship between relative concentration and temperature was not significant statistically. Also, the relationship of relative concentration and relative humidity was not significant. Mass concentration and relative concentration were 5.31+/-5.22 mg/m3 and 162+/-163 CPM (Mean+/-Standard deviation) respectively. The range of mass concentration was 1.22-22.69 mg/m3; relative concentration 16-628 CPM. The relationship of mass concentration and relative concentration was not significant in these ranges.

Quartz Concentration and Respirable Dust of Coal Mines in Taeback and Kangneung Areas / 예방의학회지

In order to investigate working conditions of underground coal mines, this work was undertaken to evaluate the respirable dust and the concentration of quartz in Taeback and Kangneung areas. The concentration of quartz was determined by Fourier Transform Infrared Spectrophotometry. The results were as follows; 1) The concentration of respirable dust of drilling and coal face in Taeback and Kangneung areas were as followed. 2) Distribution of respirable dust was well fitted to the long-normal distribution and geometric mean value was log(-1) 0.37+/-log(-1) 0.47 (2.34+/-2.95) mg/m3. 3) The difference of respirable dust concentrations in Taeback and Kangneung areas was not significant statistically (p>0.05). 4) The concentration of quartz of drilling and coal face in Taeback and Kangneung areas were as followed. 5) Distribution of quartz concentrations was well fitted to the log-normal distribution and geometric mean value was log(-1) 0.33+/-log(-1) 0.45 (2.14+/-2.82)%. 6) The difference of quartz concentrations in Taeback and Kangneung areas was not significant (p>0.05), but significant at drilling sites and coal faces (p<0.05).