SINGAPORE - The haze that envelops Singapore for the past week hits unhealthy levels on Wednesday (Sept 18) morning as workers head to work and students to school.
The 1-hour PM2.5 reading ranged between 82 micrograms per cubic metre in the northern part of the island and 94 in the southern part, within the elevated band, at 7am.
The 24-hour Pollutant Standards Index (PSI) was 100 in the central region and higher across the island. The highest reading of 116 was recorded in the south.
A PSI reading of 101 to 200 is in the unhealthy range, for which the National Environment Agency (NEA) advises the public to cut down on outdoor activities.
There are four bands on the PM2.5 concentration scale: 0 to 55 for normal, 56 to 150 for elevated, 151 to 250 for high, and very high for readings above 250.
The five bands on the PSI scale are: 0 to 50 for good, 51 to 100 for moderate, 101 to 200 for unhealthy, 201 to 300 for very unhealthy, and hazardous for readings above 300.
The NEA said yesterday that a government task force that it leads is ready to tackle the impact of haze, and the 24-hour PSI is forecast to range between the high end of moderate range and the low end of unhealthy range, and depending on wind conditions.
This article was first published in The Straits Times. Permission required for reproduction.