The Malaysian palm oil industry is a large sector contributing to the economic growth of the country. As the world’s second largest palm oil producer with millions of hectares of plantations, approximately 20 million tonnes of crude palm oil (CPO) was produced in 2014 from 439 palm oil mills (MPOB, 2014). As a result, the palm oil industry is identified as a major contributor to water and air pollution. The sources of air pollution in the palm oil mills are mainly from boilers using fibres and shells as fuel, and incinerators burning empty fruit bunches (Abdullah et al., 2007).