Stack Emission monitoring is often referred to the air monitoring of an emission point. Typically, such monitoring is carried out on boiler stacks, exhausts from printers, discharges from bag filters, thermal oxidizers etc. and is performed on a regular, monthly or as per requirement.

Stacks from boilers and industrial processes will carry pollutants such as SOx, NOx, particles, solvents and other gases.  These can have a detrimental effect on local air quality and for this reason such emissions are often regulated. The purpose of the monitoring will be to determine whether the emissions are below the limits.