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; Arithmetic $Mean{pm}S.D.(mg/m^3)$ Taeback Drilling: $2.00{pm}1.56$ Taeback Coal Face: $3.74{pm}3.14$ Kangneung Drilling: $4.55{pm}4.51$ Kangneung Coal Face: $5.77{pm}4.53$ Geometric $Mean{pm}S.D.(mg/m^3)$ Taeback Drilling: $1.34{pm}2.81$ Taeback Coal Face : $2.55{pm}2.61$ Kangneung Drilling : $2.44{pm}3.63$ Kangneung Coal Face: $4.24{pm}2.37$ 2) Distribution of respirable dust was well fitted to the log-normal distribution and geometric mean value was $log^{-1};0.37{pm}log^{-1};0.47(2.34{pm}2.95)mg/m^3$. 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; Arithmetic $Mean{pm}S.D.(%)$ Taeback Drilling: $6.18{pm}5.52$ Taeback Coal Face: $1.89{pm}1.54$ Kangneung Drilling: $3.54{pm}2.12$ Kangneung Coal Face: $2.05{pm}3.37$ Geometric $Mean{pm}S.D.(%)$ Taeback Drilling: $4.24{pm}2.59$ Coal Face: $1.39{pm}2.22$ Kangneung Drilling : $2.55{pm}3.08$ Kangneung Coal Face : $1.24{pm}2.33$ 5) Distribution of quartz concentrations was well fitted to the log-normal distribution and geometric mean value was $log^{-1};0.33{pm}log^{-1};0.45(2.14{pm}2.82)%$. 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).