A set of chemical accidents is retrieved from the literature and classified with regard to the substance involved and whether domino effects are present. This set of accidents and each of the classes defined are statistically analyzed with respect to its severity and comparison is made between domino and non-domino accidents. The analysis reveals that each accident category shows characteristic patterns in terms of fatalities caused and domino effects likelihood. Moreover, chemical accidents severity frequencies are described by using a two-parameter, revised form of the Pareto probability density function. The range within which the values of the parameters lie is investigated using Bayesian inference.