A New Experimental Method for the Determination of Emittable Initial VOC Concentrations in Building Materials and Sorption Isotherms for IVOCs

This paper describes a new experimental method for determining the initial concentrations of emittable volatile organic compounds (VOCs) from building materials and sorption isotherms for individual VOCs (IVOCs), which are required for modeling the VOC emission rates of building materials and assemblies. The method is also useful for the rapid screening of materials, enabling manufacturers to compare different production processes in order to reduce VOC emissions from their products. In this experimental method, material specimens were first ground into powder form in a sealed container and then allowed to emit in a recirculation loop to measure equilibrium concentrations at different levels, as well as the accumulated emission mass. Test results for particle board are presented, and compared to those obtained from a 30 day small chamber emission test for the same material. Results showed that the extraction method significantly increased the release of VOCs from the material and can be used to determine the total emittable initial VOC concentrations and the sorption isotherms for acetaldehyde and hexanal. For formaldehyde, the residual amount after the extraction test was found to be significant, and requires further investigation. Further studies are needed to shorten the test time and determine the accuracy and repeatability of the extraction method.