This work predicts the flash points of partially miscible aqueous-organic mixtures using the flash point prediction model of Liaw et al. (J. Chem. Eng. Data 55 (2010) 3451-3461) handling non-ideal behavior through liquid phase activity coefficients evaluated with UNIFAC-type models, which do not need experimentally regressed binary parameters. Validation of this entirely predictive model is conclusive with the experimental data over the entire flammable composition range for 10 aqueous-organic binary and ternary mixtures. Overall, the model describes the experimental data of flash point well when using UNIFAC-type models to estimate the activity coefficient. If the LLE UNIFAC parameters are not accessible, a model based upon the VLE UNIFAC parameters provides an acceptable means of predicting flash point for partially miscible aqueous-organic mixtures, as revealed by a comparison between predicted and experimental data. (C) 2013 Elsevier B.V. All rights reserved.