A new simple correlation is introduced for predicting electric spark sensitivity of nitroaromatic compounds. This approach is based on the number of carbons and hydrogens as well as the ratio of hydrogens to oxygens and the presence of certain groups, i.e. alkyl or alkoxy groups, attached to an aromatic ring. The model is optimized using a set of 17 polynitroaromatic explosives as training set and then it is applied to 14 explosives from a variety of chemical families as test set in order to assess the predictive capability of new method. Predicted results are reasonably close to the measured values for both training and test sets. (c) 2007 Elsevier B.V. All rights reserved.