A proposed correlation equation is presented in the present note, based on our previous paper [Y.I. Chang, H.C. Chan, Correlation equation for predicting filter coefficient under unfavorable deposition conditions, AIChEJ.54 (2008) 1235-1253]. When comparing with available filtration experimental data for both large and small particles, we find that the present proposed correlation equation can give a better prediction on the filter coefficient than the equation presented in our previous paper. (c) 2008 Elsevier B.V. All rights reserved.