Documentation Of Field And Laboratory Emission Cell "FLEC": Identification Of Emission Processes From Carpet, Linoleum, Paint, And Sealant By Modeling

Abstract

Time versus concentration data of selected volatile organic compounds (VOCs) emitted from four pre-conditioned building materials were measured in the Field and Laboratory Emission Cell (FLEC) at three air exchange rates, 171, 342, 684 h−1, respectively, during a period of 240 hours. The materials were a carpet, a linoleum, a water-borne paint, and a sealant. Modeling of the time versus concentration data for two air exchange rates showed that the emission of VOCs from the carpet were best described with a diffusion model in which the diffusion coefficient depends on the concentration gradient for all data (exponential diffusion model), while a reduced data set eliminating initial events also could be described with a first order decay incorporating a sink effect. The paint emission data of the polar semi-VOC, Texanol, could be described with a first order decay model incorporating a sink effect for all three air exchange rates. The emission rate constant doubled by doubling the air exchange rate. The emission data for VOCs from the sealant were best described for all three air exchange rates by the exponential diffusion model. The best model correlation fit was obtained for hexane, but satisfactory results were also obtained for 2-ethylhexanol and dimethyloctanols. The decay results of linoleum did not allow for modeling leading to the conclusion that an internal concentration gradient had not yet been established under the experimental conditions