Haze update Sept 19: Air quality turns unhealthy in central Singapore; 24-hour PSI forecast in high-moderate to mid-unhealthy range
Air quality in the Republic worsened on Saturday (Sept 19) afternoon as the 24-hour Pollutant Standards Index (PSI) in central Singapore entered the unhealthy range at 1pm.One-hour PM2.5 in the central region also bordered the high-band at 12pm, hitting a high of 149 µg/m3. Readings between 56 and 150 are in the elevated band.At 6pm, the 24-hour PSI reading ranged from 83 to 108. This is in the moderate to unhealthy range. The highest PSI reading of 108 was recorded in central Singapore, while the next highest readings were in eastern (93) and western (96) Singapore. Meanwhile, one-hour PM2.5 is in the normal band for all regions, except in central Singapore, where the concentration reading is 61.In its daily haze update on Saturday evening, the National Environment Agency (NEA) said the country's 24-hour PSI forecast is expected to remain in the high-moderate to mid-unhealthy range.