Singapore’s air quality remained in the unhealthy range on Sept. 30, with four of the island’s five regions recording 24-hour Pollutant Standards Index readings above 100.
The National Environment Agency said air quality had improved slightly compared with the previous day but remained mostly unhealthy. The northern region was the exception, with its reading falling below the unhealthy threshold.
The haze has been linked to moderate to dense smoke from fires in Kalimantan and southern Sumatra. Dry conditions in those areas are expected to continue, while prevailing easterly and southeasterly winds could continue carrying smoke towards Singapore despite showers forecast over the island.
On Sept. 29, Singapore’s 24-hour PSI ranged from 107 to 157 in the unhealthy band. The NEA’s forecast for the following 24 hours remained between the high end of the moderate range and mid-unhealthy levels.
Under Singapore’s air-quality guidelines, a 24-hour PSI reading from 101 to 200 is classified as unhealthy. The NEA advises healthy people to reduce prolonged or strenuous outdoor physical activity during unhealthy periods, while elderly people, children, pregnant women and those with chronic heart or lung conditions are advised to take greater precautions.
The agency also recommends checking the one-hour PM2.5 reading for immediate outdoor-activity decisions because it provides a more current measure of fine-particle pollution. On Sept. 29, one-hour PM2.5 readings were in the normal to elevated bands.
With dry weather continuing in parts of Sumatra and Kalimantan, Singapore’s haze conditions could remain variable in the coming days depending on rainfall and wind direction.
