Moderate 24-hour PSI across Singapore on Sept 7 morning, 1-hour PM2.5 in normal range
For the second consecutive morning in Singapore on Monday (Sept 7), air quality over 24 hours has remained in the moderate range — albeit on the higher end of the range.At 10am, the central region recorded a 24-hour Pollutant Standards Index (PSI) reading of 92.Meanwhile, 24-hour PSI readings in the northern, eastern, southern and western regions are 68, 86, 78, and 86 respectively.Air quality hit the unhealthy range of 100 to 200, for the first time since October 2023, last Friday morning — recording a 24-hour Pollutant Standard Index (PSI) reading of 103.During that period, 1-hour PM2.5 readings in the central and eastern regions also hit the elevated range.But the situation improved from Saturday night, with data from the National Environment Agency's (NEA) haze microsite showing that 24-hour PSI readings fell back below the unhealthy range from about 9pm on Saturday.