KUALA LUMPUR, Sept 27 — The natural resources and environment ministry today insisted that the air pollutant index (API) readings updated periodically on the Department of Environment’s website are accurate.

The ministry said in a statement that visibility and API readings may not necessarily correlate as both aspects are measured differently.

It stressed that API readings are based on the amount of dust particles measuring smaller than 10 micrometres (PM10) over a 24-hour period — which is then used to calculate the level of risk on public health.

Visibility, meanwhile, is measured over a short period by the Malaysian Meteorological Department, the ministry added.

Advertisement

“Referring to public complaints on the accuracy of the API readings on the Department of Environment’s website, we would like to inform that the API readings put up are accurate and based on international protocols,” the statement read.

The statement also cited the Met Service as saying that states in the peninsula’s west coast and Sarawak’s western region may continue to experience haze up till October 2 if open burning persists in Sumatera and Kalimantan in neighbouring Indonesia.

Earlier today, the education ministry ordered the closure of all schools in Selangor, Negri Sembilan, Putrajaya and Kuala Lumpur and in the districts of Sri Aman and Kota Samarahan in Sarawak as API readings spiked to unhealthy levels.

Advertisement

The haze reading in Shah Alam reached a very unhealthy level with an API of 281, with many parts of the peninsula also registering deteriorating levels.

Port Klang also recorded a bad API at 252.

As of 1pm today, the API in Kuala Selangor registered 168, Seremban recorded 152, Tanjung Malim 147, Port Dickson 131 and Jerantut 122, all falling under the unhealthy category of the API.

An API reading of 0 to 50 indicates good air quality; 51 to 100, moderate; 101 to 200, unhealthy; 201 to 300, very unhealthy and 300 and above, hazardous.