This paper presents a new model for airborne nanoparticle filtration by considering the effects of capillary force and plastic behavior impaction. This model was also validated using experimental data in literature and that collected by the authors. Results show that the capillary force between particle and the filter surface increases with the relative humidity level, leading to reduced rebound of nanoparticles from a filter media. Therefore, thermal rebound of nanoparticles may only occur at low relative humidity conditions. (C) 2015 Elsevier Ltd. All rights reserved.