The rain over the past week has brought some relief from the haze plaguing Singapore.
But as the haze in the region is more severe compared to last June's episode, the Ministry of the Environment and Water Resources (MEWR) and the National Environment Agency (NEA) are bracing for conditions to worsen in the months ahead.
At a media briefing on Thursday, Minister for the Environment and Water Resources Vivian Balakrishnan said while the rain may have "improved" the situation brought on by a prolonged dry spell, the improvement is also likely to be "temporary".
In view of this, both MEWR and NEA are rolling out the new Pollutant Standards Index (PSI) a month earlier than scheduled.
It will come into effect from April 1 instead of May 1.
The new air quality reporting system incorporates PM2.5 into the current Pollutant Standards Index (PSI) as its sixth pollutant parameters.
PM2.5 refers to particulate matter up to 2.5 micrometres or microns in size.
These particles are known to cause inflammatory responses both in the respiratory tract and blood vessels.
Previously, the incidence of PM2.5 was not directly taken into account when determining the index.