The haze descended on Singapore again yesterday and looks set to continue today.
Air quality reached the worst levels so far this year with the three-hour Pollutant Standards Index at an unhealthy 153 at 7pm yesterday.
At such levels, healthy people should reduce prolonged or strenuous outdoor physical exertion. Older folk, pregnant women and children should minimise such activity, while those who do not feel well or have chronic lung or heart conditions should avoid it.
The National Environment Agency (NEA) said that the pollution was due to smoke haze blown from central Sumatra by prevailing south-westerly winds. This is expected to continue today, with overall air quality expected to be in the unhealthy range.
The total number of hot spots detected in Sumatra and Kalimantan was 97 and 74 respectively, said the NEA yesterday.
The levels of PM2.5, which are small, toxic particles, were also elevated across the island yesterday, with the one-hour concentration of the particles rising to 131 micrograms per cubic metre in the southern areas at 6pm. A reading above 55mcg is considered unhealthy.
Before yesterday, the highest three-hour PSI reading this year was 129 last month. Last year's record was 401 in June.
Even so, activities at mosques over the Hari Raya Haji holiday went on smoothly yesterday. "Everything went well," said Imam Habib Hassan of Ba-Alwie Mosque in Bukit Timah. "Most of the prayers were held indoors, so there was no problem."
Some businesses with outdoor activities, however, saw a dip in customers. Italian restaurant Casa Verde, which has outlets in the Singapore Botanic Gardens and Gardens by the Bay, had a 20 to 30 per cent drop in customers yesterday, while cable-ski park Ski360 Degree in East Coast Park said sales dropped by around 10 per cent.
But the pollution failed to deter many people, who were determined to stay outdoors and enjoy the public holiday.
When The Straits Times visited Orchard Road yesterday afternoon, the outdoor walkways were packed.
And in the evening, around 400 people showed up for band performances at the Marina Bay Sands Waterfront Promenade.
Housewife Cheren Wong, 47, was there with her two sons, aged 15 and 17. "It was okay, as long as the PSI did not climb to over 200," she said. "If it continues to climb, it will definitely be a concern."
PSI readings of 201 to 300 are considered very unhealthy, and people are advised to wear an N95 mask if they have to be outdoors for several hours.
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