SINGAPORE - Hazy conditions are expected to continue on Friday (Sept 2), with the 24-hour Pollutant Standards Index (PSI) set to be between the high end of the unhealthy range and the middle of the very unhealthy range.

In its 5pm advisory on Thursday (Sept 1), the National Environment Agency (NEA) added that the 24-hour PSI could deteriorate to the high end of the very unhealthy range if denser haze is blown in by prevailing winds from the south-east or south.

The situation did not improve on Thursday as the 24-hour reading entered the very unhealthy range at noon, before decreasing slightly at 3pm.

As of 4am, the 24-hour PSI was 131-166, with the three-hour PSI at 114.

With the start of Primary School Leaving Examination (PSLE) on Thursday, primary schools in Singapore are taking extra precautions for the safety of staff and pupils.

The pupils will sit their exams in air-conditioned facilities - from school halls to special classrooms - and these are fitted with air purifiers.

There are already processes in place for candidates who are ill during national exams, and these will apply to those unable to take the exam due to haze-related illnesses.

For updates, visit the NEA website and the haze microsite, and follow NEA's Facebook page or Twitter account, or download the myEnv app.