Status of air quality before and during reinforcement of MCO due to COVID-19 outbreak in Central and Southern Regions of Peninsular Malaysia

Abstract

The first confirmed case of Coronavirus-19 (COVID-19) in Malaysia was reported on January 25, 2020, and the number of cases has been steadily increasing since March 2020. To minimize the spread of COVID-19, the Malaysian government implemented a Movement Control Order (MCO), effective on 18 March 2020. The MCO was extended multiple times and has, at times, switched to either the Conditional Movement Control Order (CMCO), the Recovery Movement Control Order (RMCO), or the Enhanced Movement Control Order (EMCO). As a result, there were fewer motor vehicles on the road, and industry operations were halted, resulting in lower hazardous emissions. Therefore, this study intends to investigate the air quality index (AQI) before and during MCO implementation. Air pollution has become a more worrisome problem in urban areas, especially from vehicle discharge. The data set of the daily average AQI in Kuala Lumpur, Petaling Jaya, Putrajaya, and Johor Bahru was analyzed using the paired t-test and independent t-test. The analysis showed that the AQI of the cities is normally distributed. The result showed a significant difference in daily AQI before and during the reimplementation of MCO in Kuala Lumpur. Apart from that, a comparison between urban areas with MCO and without MCO only shows a significant difference between Kuala Lumpur and Johor Bahru. The finding revealed that MCO is capable of reducing the AQI in Kuala Lumpur. Therefore, the government can plan strategies that are related to reducing the number of activities and carbon emissions such as increasing the utilization of public transport.