Haze in Singapore: Air quality across island remains unhealthy overnight

SINGAPORE – The haze situation here did not ease overnight as the air quality across the island remained in the unhealthy range.

As at 6am on Oct 9, the 24-hour Pollutant Standards Index (PSI) readings stood at 109 in the north, 135 in the south,134 in the east, 155 in the west and 159 in the central region.

Air quality is considered unhealthy when the PSI – a 24-hour rolling average of six key air pollutants – is in the range of 101 to 200.

Meanwhile, PM2.5 readings were elevated across all regions in Singapore, led by the west at 143, central at 140, south at 134, east at 117 and north at 92.

The hourly PM2.5 reading is used as a gauge for immediate air quality, with scores from 56 to 150 indicating elevated pollution levels while values of 151 to 250 represent high pollution levels.

The highest PSI reading of the year – 167 in central Singapore – was recorded on Sept 29. That same day, the central region also saw the highest 1-hour PM2.5 reading of 2026 of 165 at midnight.

In its daily advisory on the evening of Oct 8, the National Environment Agency (NEA) forecast that the 24-hour PSI readings will be in the high moderate to mid-unhealthy range.

NEA said moderate to dense smoke plumes from southern and central Sumatra and West Kalimantan were observed to be drifting towards Singapore, with dry conditions expected to continue in the neighbouring Indonesian territories.

“Under the prevailing south-easterly or southerly winds, smoke haze may continue to drift towards Singapore,” it added.