Continuous Emissions Monitoring System

A continuous emissions monitoring system, or CEMS, is used to monitor the effluent gas streams produced by combustion in industrial processes, typically measuring flue gas for oxygen, carbon monoxide and carbon dioxide to provide real time information for combustion control. CEMS installations are also used to demonstrate compliance with air emission standards, including the United States Environmental Protection Agency Acid Rain Program, other federal emission programs and state permitted emission limits. A complete system typically comprises analyzers, sample conditioning equipment, pneumatic systems with valve controls, calibration mechanisms and a data acquisition system that collects and stores emissions information on a continuous basis, giving plant operators and regulators a running record rather than periodic spot checks.