New Malaysia Ambient Air Quality Standards 2020 stated that factories need to conduct environmental testing for ambient air quality surrounding employee outdoor. The Standard adopts 6 pollutants criteria that includes particle matter with size less than 10 micron (PM10), Sulphur dioxide (SO2), carbon dioxide (CO2), nitrogen dioxide (NO2), ground level ozone (O3) and particle matter with size less than 2.5 micron (PM2.5).