The haze has returned to Singapore after a day of relatively clear skies, as air quality broke into the "moderate" range on Sunday evening.
As of 6pm, the Pollutant Standards Index's (PSI) three-hour reading stood at 54, up from the 24 it registered at 9am.
According to the National Environment Agency's (NEA) website, all persons - regardless of age or health conditions - can continue to take part in normal activities during good and moderate PSI levels.
In a haze situation update on March 8, the NEA said that the haze could be due to the prevailing northeasterly winds bringing in the smoke from hotspots north of Singapore. A total of 14 hotspots were detected in peninsular Malaysia and 129 in Sumatra then.
The Riau province of Sumatra has been shrouded in dense haze over recent days as farmers set fires to clear land during the dry spell.
On Friday, air quality reached the worst level since the start of the year, with the haze affecting visibility and some complaining of a burning smell. The PSI reading hit a high of 71 at 8pm on Friday, and fell to 61 two hours later.
Haze situation updates can be accessed from NEA's Facebook and Twitter accounts, or at the haze microsite at www.haze.gov.sg