Singapore's air quality hits unhealthy range, 'slightly hazy' conditions forecast for Saturday

SINGAPORE: The air quality in Singapore entered the unhealthy range on Saturday (Oct 7), as authorities warned of hazy conditions due to a rise in the number of hotspots in Indonesia.

At of 4pm, the 24-hour Pollutant Standards Index (PSI) for the eastern and central regions of Singapore were 119 and 110 respectively. The National Environment Agency (NEA) regards a reading of 101-200 as "unhealthy". 

The one-hour PM2.5 readings showed elevated levels in the eastern (90) and central (94) areas. A reading of between 56 and 150 is considered elevated.

The 24-hour forecast as of 8.30am on Saturday was for "slightly hazy" conditions in the north, south, east and central parts of Singapore, with only the west experiencing partly cloudy conditions. 

NEA said late on Friday that air quality could enter the unhealthy range this weekend if forest fires persist in Indonesia, coupled with unfavourable wind direction.

The agency noted a "significant increase" in the number of hotspots in Sumatra, with 212 detected on Friday compared with 65 on Thursday and 15 on Wednesday.

"Smoke plumes and haze were observed from satellite imagery over southern and central Sumatra. A brief shift in the wind direction this afternoon, from southeasterly to southerly, blew some of the lighter haze toward Singapore and caused a deterioration in air quality," it said in a media release.

"There is a likelihood of haze affecting Singapore over the coming weekend if the fires persist and winds direction is unfavourable."

The 1-hour PM2.5 levels in the southern and eastern parts of Singapore had entered elevated levels - above 55 ug/m3 - on Friday afternoon and remained elevated at 10pm.

The agency added that it will begin providing daily haze advisories from Saturday evening.

The daily haze advisory will include the 24-hour PSI forecast, which can be used by the public in planning their activities and events for the next 24 hours.

"Advisories have earlier been issued to various sectors including healthcare institutions, preschools, schools and workplaces to remind them to take appropriate haze management measures should the 24-hour PSI enter the unhealthy range, especially to protect more vulnerable groups," said NEA.

The last time the 24-hour PSI was higher than 80 was in 2019. 

NEA said last Friday that the government’s Haze Task Force, made up of 28 public agencies, is ready to roll out their respective haze action plans if the air quality deteriorates into the unhealthy range.

Members of the public can check current air quality readings and advisories on www.haze.gov.sg and the myENV app.