Distribution Characteristics of the Concentration of Ambient PM-10 and PM-2.5 in Daegu Area

The three air quality monitoring sites, analysed simultaneously PM-10 and PM-2.5, ie.Ihyeondong in industrial area, Manchondong in residential area, Pyeongnidong in streetside, among 13 air quality monitoring sites in Daegu area, were investigated the concentration distribution characteristics of PM-2.5 and PM-10 in the last 2 years (2011~2012).PM-10 concentrations exceeded annual average reference value (50 µg/m 3 ) in Ihyeondong (52.5 µg/m 3 ) and Pyeongnidong (60.9 µg/m 3 ) but satisfied in Manchondong (44.9 µg/m 3 ).All PM-2.5 concentrations exceeded EPA annual standard value of the United States (15 µg/m 3 ) in three points, but also exceeded new control annual standard value (25 µg/m 3 ) coming into effect in 2015.Seasonal concentration of PM-10 appeared the order of spring > winter > fall > summer, and in the case of PM-2.5, the order was winter > spring > fall > summer.Monthly concentrations of PM-10 and PM-2.5 were highest in February and lowest in September.Diurnal concentrations of PM-10 and PM-2.5 increased from 7:00 AM, and recorded the highest concentration between 10:00 AM and 11:00 AM.And after 6:00 PM it lowered continuously and tended to show fixed concentrations from evening until early morning.In addition, the concentration of fine particles during the week was higher than the weekend.The fluctuation in industrial area was larger than the residential area.At the PM-2.5/PM-10ratio, summer was generally high, spring was the lowest.And, when yellow sand occurred, it was 0.32 to 0.42.It was very low compared to 0.54 to 0.64 during non-yellow sand times.This paper for the state and the characteristics of Daegu' fine particles (PM-10, PM-2.5) will be valuable to future researches of fine particles and air pollution management. Key Words : PM-