Haze watch Oct 9: Central Singapore PSI rises to record 191, just shy of 'very unhealthy' range
Air quality in the Republic is deteriorating towards the very unhealthy range, with the 24-hour Pollutant Standards Index (PSI) in central Singapore rising to 191 by 4pm on Friday (Oct 9) afternoon, up from 181 at noon.The latest reading marks a new high for 2026, surpassing the record of 181 set earlier in the day and placing air quality just 10 points away from the very unhealthy range.At 4pm, PSI in all five regions remain in the unhealthy range, with the next highest reading of 183 recorded in western Singapore.Readings of 201 to 300 denote the very unhealthy range.Meanwhile, one-hour PM2.5 concentrations remained in the elevated band in all five regions.The highest concentration reading of 148 was recorded in western Singapore, followed by 145 in central Singapore.Concentration readings between 56 to 150µg/m3 fall within the elevated band, while readings between 151 and 250 are in the high band.When one-hour PM2.5 concentration readings are in the high band, healthy persons should avoid strenuous outdoor activity for the next hour, while vulnerable persons should avoid all outdoor activity for the next hour.