SINGAPORE, Oct. 9 -- Singapore's haze showed no signs of easing this morning, with air quality remaining unhealthy across all five regions and pollution in the central region approaching its highest level this year.

At 8am, the 24-hour Pollutant Standards Index (PSI) in the central region stood at 166, just one point below the year's peak of 167 recorded there on September 29, according to The Straits Times.

The west recorded a PSI of 161, followed by the south at 145, east at 140 and north at 113.

Air quality is classified as unhealthy when the PSI, which measures six major pollutants over a rolling 24-hour period, falls between 101 and 200.

Pollution levels have remained largely within the unhealthy range across Singapore over the p...