Haze in Singapore: Air quality unhealthy across the island

SINGAPORE - The air quality in Singapore improved marginally overnight but still remained within the unhealthy band on the 24-hour Pollutant Standards Index early on Oct 10.

At 7am, the PSI readings were: north (125), south (141), east (157), west (162), central (176).

Air quality is considered unhealthy when the PSI - a 24-hour rolling average of six key air pollutants - is in the range of 101 to 200.

PM2.5 readings, which point to the current air quality and are used as a gauge for immediate activities, were also elevated in all five regions: north (69), south (89), east (112), west (104), central (124).

An hourly PM2.5 reading between 56 and 150 indicates an elevated concentration of fine particles.

The PSI had hit a high for the year on Oct 9, reaching 192 on the PSI in the central region between 5pm and 8pm.

In its Oct 9 daily advisory, the National Environment Agency (NEA) had forecast the PSI for Oct 10 to lie in the “unhealthy to low very unhealthy range”.

When the 24-hour PSI readings are in the unhealthy range, those who are healthy should reduce prolonged or strenuous outdoor physical activities, according to the National Environment Agency’s (NEA) haze advisory.

Vulnerable people – including the elderly, pregnant women, children and those with chronic lung or heart disease – should minimise or avoid such activities entirely.

When PM2.5 readings are high, people should avoid strenuous outdoor activities for the next hour. Vulnerable people should avoid all outdoor activities.

The government’s haze task force announced a series of measures on Oct 9 should the PSI exceed 200 and move into the very unhealthy range.

The task force, which includes agencies such as the Ministry of Education, Sport Singapore, the Ministry of Defence and Ministry of Health, said that N95 masks will be distributed to eligible Singaporeans who may be more vulnerable to the effects of haze or who may have limited means of obtaining them.

In schools, classroom lessons will continue but might be modified and outdoor activities will be curtailed.

For children in pre-schools, all outdoor activities and strenous indoor activities will cease.

Sport organisers and facility operators were also urged to consider modifying or suspending activities held outdoors and in non air-conditioned facilities.

The task force last issued an update on Sept 4, when air quality in Singapore breached unhealthy levels for the first time since October 2023.

Rhea Yasmine is a journalist at The Straits Times. She covers local and international issues, with an interest in South-east Asia.