An improved mass transfer model which considers the air-material mass transfer resistance was used to analyze volatile organic compound (VOC) emissions from building materials. The results showed that the dimensionless emission rate of VOCs is only a function of the ratio of mass transfer Biot number to the partition coefficient and of mass transfer Fourier number. These two parameters were used to fit experimental data for empirical correlations of VOC emission data. Numerical results, which agreed well with the experiment data, were used to develop several correlations describing the VOC emission characteristics from building materials. (C) 2003 Elsevier Ltd. All rights reserved.