Department of Environmental Conservation

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CEM / Stack Test Oversight & Review

The CEM/Stack Test Section provides support to staff in DEC Regional Offices by reviewing stack test protocols and reports and reviewing Continuous Emission Monitoring (CEM) system designs and reports.  Stack tests are short term sampling programs of actual emissions for pollutants, such as particulates. Testing of emissions control equipment to determine capture and/or destruction efficiency is required by some regulations and permits. Testing can also consist of sampling and laboratory analysis of coatings or inks to determine hazardous or volatile organic compound content.

Continuous emissions monitors are permanently installed devices which extract and analyze samples of stack gases several times each hour for concentrations of compounds, such as nitrogen oxides and sulfur dioxide. When these monitors are combined with flow monitors, emission tonnages can be calculated and compliance with acid rain limits can be determined. These monitors are checked frequently with gases of known concentrations to ensure the system is calibrated and the emissions data produced is accurate.

Continuous opacity monitors are required on large sources of particulate emissions to document compliance with regulations and permits. These units measure and record visible emissions which can occur due to an upset event, start up or maintenance procedures.