A significant source of odour is from landfills. Today, when we pass from any such solid waste dump yards, we are pushed to discomfort as we smell various odours for a few seconds. Also, underperforming or non-performing Sewage Treatment Plants and Effluent treatment plants tend to release unwanted odours in the air leading to harmful atmospheric conditions for the residents nearby. The state even gets worse when combined with the industrial odours, forming a dangerous combination that sometimes leads to fatality. Odour monitoring in these cases is an excellent assessment and helps take corrective actions.