SINGAPORE: Air quality in Singapore moved into the "unhealthy" range on Monday (Sep 15), with the Pollutant Standards Index (PSI) three-hour reading hitting 113 at 6am. As of 7am, the three-hour reading was 111.
The 24-hour PSI reading as of 7am on Sep 15.
The three-hour PSI reading was 64 at 6pm on Sunday and it climbed to 74 at 9pm Sunday. It has since remained in the 101-200 range.
The 3-hour PSI reading as of 7am on Sep 15.
A PSI reading of 0-50 is considered "good", 51-100 is classified as "moderate", while 101-200 is in the "unhealthy" band.
The National Environment Agency (NEA) has advised healthy people to reduce prolonged or strenuous outdoor physical exertion when the PSI is in the "unhealthy" range. The elderly, pregnant women and children should minimise such activities, which should also be avoided by people with chronic lung disease or heart disease, NEA said on its website.
Environment and Water Resources Minister Dr Vivian Balakrishnan wrote in a Facebook post on Monday morning that he was monitoring the air quality with "some concern".
His post said a change in wind direction brought with it haze that had been accumulating over Sumatra for the past few days, with the western parts of Singapore especially affected, he wrote.
"There has been an escalation in hot spots in Sumatra. NEA was in touch with the Indonesian authorities last week and has urged them to take action," he wrote, adding that Singapore "stands ready" to provide assistance if necessary.