Flux Chambers are used to determine levels of volatile organic compounds emitted from land or liquid surfaces. The Flux Chamber is set up to enclose a known surface area. Air is introduced to the chamber to mix with the emissions and transport them to the collection devices. The Chamber is designed to create the best mixing and sampling conditions without altering the emission of gases at the surface. The samples collected are used to determine the actual flux of pollutants at the surface. i.e. ug / m2 / min.

System Blanks and Calibrations prior to Sampling are critical in ensuring the chambers are ;operating correctly.

The Flux Chamber enables measurement of emission rates for a wide range of compounds, from a range of sources. These can include:

• Contaminated Sites
• Landfill Sites
• Land Treatment
• Water Treatment Ponds

Analysis of the sorbent sampling tubes for Volatile Organic Compounds by Themal Desorption according to US EPA TO-17 provides the lowest possible detection limits for VOCs. Samples are collected in duplicate, in the form of "Distributed Volume Pairs" to assist in validating the sampling procedures and adding another level of quality control.

U.S. EPA 1989. Risk Assessment Guidance for Superfund, Vol I: Human Health Evaluation Manual, Part A, Interim Final, U.S. Environmental Protection Agency, Washington, D.C.(EPA/540/1-89/002).

Case Study Comparisons of Vapor Inhalation Risk Estimates: ASTM RBCA Model Predictions Vs Site Specific Soil Vapor Data. P.J McNeel & C Atwood ,Weiss Associates. V Dibley, Lawrence Livermore National Laboratory.