Abstract = The
concentrations of selected volatile organic compounds (VOC) were measured
from four preconditioned materials in the Field and Laboratory and Emission
Cell (FLEC). The materials were a carpet, a linoleum, a waterborne paint,
and a sealant. Measurements were carried out at three different air exchange
rates, 171, 342, 684 h-1, respectively, and measured during a period of
six days. Modelling of the concentration vs. time data for two air exchange
rates showed that the emission of VOC from the carpet were best described
with a diffusion model for all data while a reduced data set eliminating
initial events also could be described with a first order decay incorporating
a sink effect. The decay 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. However, the rate constant doubled by doubling the
air exchange rate. The decay data for VOC from the sealant were best described
for all three air exchange rates with a diffusion model incorporating a
concentration gradient dependent diffusion and a reduced data set. Best
fit was obtained for the unpolar hexane, but satisfactory results were
also obtained for 2-ethylhexanol and dimethyloctanol. The decay results
of linoleum did not allow for modelling leading to the conclusion that
an internal concentration gradient had not yet been established under the
experimental conditions. |