The three-hour Pollutant Standards Index (PSI) remains in the "hazardous" range, rising to 326 at 10am on Saturday, up from 292 an hour earlier.

The 24 hour average PSI at 9am was in the 177-241 range, a slight decrease from 179-246 at 8am.

Some grassroots groups were meeting early Saturday morning ahead of the distribution expected to start later today with the Singapore Armed Forces helping with the roll-out.

Tanjong Pagar GRC MP and Acting Minister for Social and Family Development Chan Chun Sing, was at Buona Vista Community Club briefing some 80 grassroots leaders ahead of the distribution of the masks, while Second Minister for the Environment and Water Resources Grace Fu met with community leaders from Yuhua on issues arising from the haze and dengue situation here.

The latest reading comes after a slight reprieve from the night when PSI levels remained under 200.

However, air is considered 'unhealthy' when PSI readings range between 101 and 200.

PSI readings hit a record high of 401 at noon on Friday. Anything above 300 is hazardous, while readings between 201 and 300 are very unhealthy.