A Continuous Emission Monitoring System (CEMS) is an integrated system to measure fuel flow, dust, and concentrations of air pollutants such as SO2, NOx, CO, CO2, THC and O2 in accordance with the applicable regulations for the emission source.

(Portable Emissions Measurement System (PEMS) for on-board measurement in response to the increasing legislative requirements to test the exhaust emissions from vehicles when driven or operated under real world conditions. The use of laboratory grade analyzers in such portable systems required the reduction of size, weight and power consumption as well as ensuring that the system had excellent resistance to shock and vibration as well as the altitude and temperature variation that is likely to occur under real world conditions.