The characteristics of PM10, PM2.5 and Ratio(PM2.5/PM10) of 11 urban air monitoring stations in Gyeongnam were analyzed for the last 3 years(`15~`17). The average of the all stations was PM10 45 μg/㎥, PM2.5 24 μg/㎥ and Ratio 0.54, and annual reduction rates were PM10 -2.9%, PM2.5 –2.7% and Ratio –1.2%, respectively. The seasonal characteristics of PM10 were spring 54 μg/㎥ > winter 48 μg/㎥ > summer/autumn 40 μg/㎥, PM2.5 were spring/winter 26 μg/㎥ > summer 23 > autumn 22 μg/㎥ and Ratio were summer 0.56 > winter 0.55 > autumn 0.54 > spring 0.51, respectively. The hourly characteristics of PM10 were 11 μg/㎥ higher than 09:00~12:00 at 03:00~06:00, PM2.5 were 6 μg/㎥ higher than 09:00~12:00 at 17:00~18:00 and Ratio were 0.07 higher than 04:00~06:00 at 19:00. By site, the highest concentration of PM10 was YJ site 53 μg/㎥ and PM2.5 was HW site 28 μg/㎥. And Ratio at HD site showed the largest reduction from `15 0.62 to `17 0.52.

Hourly concentrations of PM1, PM2.5 and PM10, were investigated at Gangneung city in the Korean east coast on 0000LST October 26~1800LST October 29, 2003. Before the intrusion of Yellow dust from Gobi Desert, PM10(PM2.5, PM1) concentration was generally low, more or less than 20 (10, 5) μg/m3, and higher PM concentration was found at 0900LST at the beginning time of office hour and their maximum ones at 1700LST around its ending time. As correlation coefficient of PM10 and PM2.5(PM2.5 and PM1, and PM10 and PM1) was very high with 0.90(0.99, 0.84), and fractional ratios of (PM10-PM2.5)/PM2.5((PM2.5-PM1)/PM1) were 1.37~3.39(0.23~0.54), respectively. It implied that local PM10 concentration could be greatly affected by particulate matters of sizes larger than 2.5 μm, and PM2.5 concentration could be by particulate matters of sizes smaller than 2.5 μm. During the dust intrusion, maximum concentration of PM10(PM2.5, PM1) reached 154.57(93.19, 76.05) μg/m3 with 3.8(3.4, 14.1) times higher concentration than before the dust intrusion. As correlation coefficient of PM10 and PM2.5(vice verse, PM2.5, PM1) was almost perfect high with 0.98(1.00, 0.97) and fractional ratios of (PM10-PM2.5)/PM2.5((PM2.5-PM1)/PM1) were 0.48~1.25(0.16~0.37), local PM10 concentration could be major affected by particulates smaller than both 2.5 μm and 1 μm (fine particulate), opposite to ones before the dust intrusion. After the ending of dust intrusion, as its coefficient of 0.23(0.81, - 0.36) was very low, except the case of PM2.5 and PM1 and (PM10-PM2.5)/PM2.5((PM2.5-PM1)/PM1) were 1.13~1.91(0.29~1.90), concentrations of coarse particulates larger than 2.5 μm greatly contributed to PM10 concentration, again. For a whole period, as the correlation coefficients of PM10, PM2.5, PM1 were very high with 0.94, 1.00 and 0.92, reliable regression equations among PM concentrations were suggested.