SHAH ALAM,  Sept 12 ― A total of 29 schools in Klang and Kuala Langat will be closed tomorrow due to haze, up from only five schools today.

The Selangor Education Department, in a statement here today, said the closure would affect  24 schools in Klang and five schools in Kuala Langat, involving a total of 45,265 students.

The standard operating procedure is for schools to close once the Air Pollutant Index (API) reading in their respective areas hits 200.

An API reading of zero to 50 indicates good air quality; 51 to 100, moderate; 101 to 200, unhealthy; 201 to 300, very unhealthy and 300 and above, hazardous.

According to the Department of Environment’s (DOE) website, the API readings at 7pm today at Johan Setia was 189, Klang (116) and Banting (111).

An API reading of zero to 50 indicates good air quality; 51 to 100, moderate; 101 to 200, unhealthy; 201 to 300, very unhealthy and 300 and above, hazardous. ― Bernama