All states recorded a moderate to healthy Air Pollutant Index (API) this morning, compared with yesterday when Port Klang reached an unhealthy level.
The Department of Environment’s website showed that only the Balak Baru, Kuantan area exceeded an API of 90 as of 7am today. API levels elsewhere ranged from 23 (Tawau, Sabah) to 86 (Batu Muda, Kuala Lumpur and Port Dickson, Negri Sembilan).
Sabah and Sarawak remain untouched by smoke, while Terengganu and a few areas in Kelantan and Johor also have healthy readings.
An API reading of between 0 and 50 is considered good; 51 and 100, moderate; 101 and 200, unhealthy; 201 and 300, very unhealthy; and 301 and above, hazardous.
The API calculation is based on five major air pollutants, namely sulphur dioxide (SO2), nitrogen dioxide (NO2), ground level ozone (O3), carbon monoxide (CO) and particulate matter below 10 micrometres (PM10) diameter.
Most of these pollutants come from sources such as industries, motor vehicles, open burning and power generation.
The concentrations of these five pollutants are measured in 52 automatic air quality stations throughout the country, mainly in industrial and urban areas.
The Star reported today that Malaysian Meteorological Department spokesman Dr Hisham Mohd Anip said the situation was likely due to weakening wind conditions, which may have caused the smoke to become stagnant.
“The dry weather has caused the dust and smoke to be suspended in the air. Strong wind for the past couple of weeks has dispersed them but the wind flow was probably weak yesterday,” the English daily quoted him as saying.
He added that the smoky condition was likely caused by local pollution, such as emissions from vehicles and factories. – June 23, 2014.