Haze in S’pore: PSI remains in unhealthy range in central region
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Hazy conditions seen from Bedok at 8am on Sept 27.
ST PHOTO: LIM YAOHUI
- Air quality in Singapore worsened on Sept 27, with PSI readings in central, eastern and western regions reaching unhealthy levels in the morning, while north and south remained moderate.
- The National Environment Agency forecast moderate to low-unhealthy air quality, citing dry conditions in nearby regions and winds bringing haze to Singapore.
- NEA advised the public to limit outdoor activities during unhealthy periods, especially vulnerable groups, and to monitor hourly PM2.5 and 24-hour PSI readings for health guidance.
AI generated
SINGAPORE – Air quality in central Singapore continued to be in the unhealthy range late on Sept 27, though the 24-hour Pollutant Standards Index (PSI) readings for the east and west has dropped from the unhealthy to the moderate band.
At 9pm, the PSI reading for the east fell to 99, below the 101 threshold for the unhealthy band, and joining the northern, southern and western regions in the moderate range at 78, 85 and 90 respectively.
The reading for central Singapore was still in the unhealthy range at 110.
The west had dropped into the moderate range at 4pm, with a reading of 100, after being in the unhealthy range since morning.
At 7am, the 24-hour PSI readings stood at 128 in the central region, 115 in the east and 106 in the west.
Readings in the north (89) and south (95) were in the moderate range at 7am.
The PSI reading for the central region started crossing into the unhealthy range at 8pm on Sept 26 when it hit 104, before inching upwards overnight and peaking at 127 at 3am.
The eastern region entered the unhealthy range (103) at midnight, while the western areas (102) followed suit an hour later.
Hourly PM2.5 readings were 29-60 as at 7am on Sept 27. At 4pm, the readings fell to between 17 and 31.
Air quality is considered unhealthy when the 24-hour PSI is in the range of 101 to 200, while an hourly PM2.5 reading between 56 and 150 indicates an elevated concentration of fine particles.
Decathlon’s inaugural Kiprun race was adjusted on Sept 27 because of the poor air quality.
The 21.1km half-marathon has been shortened to 10km, while distances for the other formats – the 10km, 5km and Kids Dash (670m) – remain unchanged.
NEA advisory
In its daily haze advisory at about 6pm on Sept 26, the National Environment Agency (NEA) said air quality in Singapore for the next 24 hours was forecast to be in the moderate to low-unhealthy range.
While some showers are forecast over Singapore and parts of the region overnight and on Sept 27, dry conditions are expected to continue over southern Sumatra, as well as southern and eastern Kalimantan.
Winds forecast to blow from the south-east or south-west could bring smoke haze to Singapore, NEA said.
It advised the public to refer to the hourly PM2.5 readings for immediate activities and 24-hour PSI ones to plan for the day ahead.
For periods when the air quality crosses into the unhealthy range, NEA has advised healthy people to reduce prolonged or strenuous outdoor activities, while vulnerable groups like the elderly, children and pregnant women, as well as people with chronic lung or heart disease, should minimise or avoid such activities altogether.
The PSI first returned to the unhealthy range on Sept 4, the first time since October 2023. Readings in the central region were the highest, peaking at 154 on Sept 15.
In its fortnightly weather forecast on Sept 16, the Meteorological Service Singapore said more showers are expected in the second half of the month, than in the first.