Small environmental chamber tests were conducted to characterize the emissi
ons of a toxic chemical compound methyl ethyl ketoxime (MEKO) - from three
different alkyd paints. It was found that MEKO emissions occurred almost im
mediately after each alkyd paint was applied to a pine board. Due to the fa
st emission pattern, more than 90% of the MEKO emitted was released within
10 hours after painting. The peak concentrations of MEKO in chamber air cor
related well with the MEKO content in the paint. Material balance showed th
at good recovery (more than 68%) was achieved between the MEKO applied with
the paint and the MEKO emitted. The chamber data were simulated by a first
order decay emission model assuming the MEKO emissions were mostly gas-pha
se mass transfer controlled. The model was used to predict indoor MEKO conc
entrations during and after painting in a test house. It was found that the
predicted lest house MEKO concentrations during and after the Fainting exc
eeded a suggested indoor exposure limit of 0.1 mg/m(3) for all three paints
. The predicted MEKO concentrations exceeded even the lower limit of a sugg
ested sensory irritation range of 4 to 18 mg/m(3) with two of the three pai
nts tested. The model was also used to evaluate and demonstrate the effecti
veness of risk reduction options including selection of lower MEKO paints a
nd higher ventilation during painting.