Air quality hits unhealthy range in central, western Singapore

On Monday (Oct 5), air quality in central and western Singapore deteriorated to the unhealthy range, according to the 24-hour Pollutant Standards Index (PSI) reading. At noon, the PSI reached 117 in the central region and 108 in the west. The rest of Singapore maintained moderate air quality. The National Environment Agency (NEA) advised people to refer to the 1-hour PM2.5 readings and personal health guide for immediate outdoor activities.

The 1-hour PM2.5 level was elevated in the west at noon and normal in other areas. NEA recommended healthy individuals limit strenuous outdoor activities for the next hour, while vulnerable people should avoid such activities. Scattered hotspots were detected in southern Sumatra and southern Kalimantan, while isolated hotspots appeared in parts of Java, Sulawesi, and the Lesser Sunda Islands. Smoke plumes drifted northward towards Peninsular Malaysia and Singapore.

Dry weather persisted across most of southern Southeast Asia, except for possible showers in northern Sumatra, Borneo, and Peninsular Malaysia. The situation is expected to worsen, with continued risks of transboundary haze. In Singapore, a 24-hour PSI reading of 101 to 200 is deemed unhealthy, while 201-300 is very unhealthy, and over 300 is hazardous.

The hourly PM2.5 level is classified into four bands: normal, elevated, high, and very high. Elevated levels range from 56 to 150, high from 151-250, and very high above that.