INVESTIGATION OF RECENT PM2.5 CHANGES IN CHONBURI PROVINCE USING EWMA CHARTS

This work focuses on investigating the recent nature and changes of PM2.5 concentrations inChonburi Province to see whether the process shift is meeting set the daily Thailand’s national airquality standard. The objective will be achieved by identifying the basic characteristics and thenmonitoring the process mean of PM2.5 concentrations in 2020 with EWMA charts. The obtainedresults reveal the EWMA charts taken by 3 air quality monitoring stations across ChonburiProvince have potential to rapidly to detect changing in the level of daily maximum PM2.5concentrations. The EWMA analysis suddenly illustrates a significant signal of daily maximumPM2.5 concentration was sharply increasing most notably 4 months of 2020; January, February,March and December for each of monitoring stations.