As part of the development of alternatives to animal testing, a workflow algorithm wasdeveloped to predict a molecule’s potential to trigger skin irritancy (SI) based on in vivoDraize legacy data (OECD TG404). A key requirement from safety evaluators was thepossibility to distinguish irritants from non irritants but also to predict the severity of effects.The workflow was developed for diverse chemical classes using a training set of chemicalsrepresentative of the cosmetic industry portfolio.