At 9pm, the PSI had soared to 290, higher than the previous peak of 226 in 1997, and entering the "very unhealthy" range of 201-300. It was a leap of 100 points from the PSI reading just an hour earlier, making some wonder if the updated reading was a typo on the NEA website.
"I thought it was actually worse in the day, though -- seems pretty impossible that there would be a hundred-point jump within an hour, coupled with the fact that it isn't that windy in the first place," said systems analyst Frederick Tang, 36.
"I thought it was a mistake at first," added communications undergraduate Gina Foo, 21, who said she had been feeling "very uncomfortable" while travelling outside during the day. "But I will definitely be wary about my plans for tomorrow, given how unpredictable the situation is."
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The PSI has been climbing steadily since Monday from 55 at 9am to 80 at 12pm and crossed into the "unhealthy" range of 105 at 3pm, according to the National Environment Agency (NEA).
Any reading between 101 and 200 is considered “unhealthy”.
Source: http://sg.news.yahoo.com/haze-reaches--unhealthy--level-in-singapore-085448213.html
