Many people in Singapore reported a burning
smell as haze readings surged early on Friday (22 Aug).
As of 10am, the 3-hour PSI level stood at 111,
according to the website of the National Environment Agency.
A 24-hour PSI reading within 101-200 would be
in the “unhealthy” level, but as of 10am it was still within the
“moderate” 51-62 range.
The PM2.5 pollution index, which measures
finer pollutants of smaller than 2.5 microns in diameter, shot up
to the “normal to elevated” Band II range of 150 in the west of
Singapore and 102 in the north from single digit levels earlier in
the morning.
PM2.5 pollutants is one of the six pollutants,
including carbon monoxide and sulphur dioxide, that the PSI
measures. Long and regular exposure to PM2.5 is linked to higher
risk of death from complications like lung cancer or heart disease.
There are four bands of measurements for the PM2.5 index.
