Specialized Stack Testing

PM10, PM2.5, and Condensable Particulate Matter Emission Testing

Air Control Techniques, P.C. contributed to the development of Method 201A promulgated by EPA in 2010 for the combined measurement of filterable PM10 and PM2.5. Air Control Techniques, P.C. developed the dry impinger method for condensable particulate matter to eliminate the large biases to higher-than-true emissions due to flaws in the 1992 version of Method 202. EPA promulgated this method as a replacement to Method 202 in 2010.

We specialize in the use of these methods in difficult applications, such as low-particulate matter loading gas turbine testing, testing in high temperature gas streams, and testing in stacks with on-going homogeneous and/or heterogeneous secondary pollutant formation reactions.

Wet Stack Filterable PM2.5 Emission Testing

Air Control Techniques, P.C. continues to work with the American Petroleum Institute and the National Council for Air & Stream Improvement on the development of a new stack testing method for measuring filterable PM2.5 emissions in moisture saturated and/or droplet-laden stacks. This method is needed to minimize the bias to higher-than-true measured stack emissions caused by EPA’s present policy to require the use of Method 5 in wet stacks and classify all measured emissions as filterable PM2.5 particulate matter.

VOC and Organic HAP Testing

Air Control Techniques, P.C. conducts tests for volatile organic compounds (VOCs) and most organic Hazardous Air Pollutants (HAPs) using EPA Methods 320 (FTIR), Method 18, Method 25A, and various NCASI methods.

Sulfuric Acid, HCl, and HF

Air Control Techniques, P.C. conducts tests for sulfuric acid using controlled condensation. Tests for HCl and HF are conducted using Method 320 (FTIR), Method 26A, and Method 13B.

Metals Including Mercury

Air Control Techniques, P.C. conducts emissions tests for metals using Method 29 and Method 30B (mercury).


Air Control Techniques, P.C. conducts compliance tests for dioxin-furans in accordance with Method 23 and diagnostic tests for dioxin-furans using modified and expanded versions of Method 23.

Visible Emissions

Air Control Techniques, P.C. has two individuals with current Method 9 certifications. We maintain a comprehensive resource file compiled over a 50-year period concerning the development, interpretation, and issues concerning visible emission observations of wet stacks, secondary plumes, positive pressure fabric filter outlets, industrial unpaved roads, and other complex applications of Method 9.