Abstract Process safety analysis is an information intensive task. Collecting all the necessary information from different sources is time consuming and error prone. Most of the information may already be available in some electronic formats. Sharing and reusing this process information can save significant time and effort. Using ontology can greatly enhance the communication and inter-operability among different systems. In this work, ontologies are designed for various kinds of process information and safety analysis results. PHASuite, an intelligent software system for performing automated process safety analysis, has been built based on these ontologies. Appropriate information sharing schemes have been proposed and implemented in PHASuite. It is found, based on several industrial case studies, that information sharing can greatly reduce time and errors associated with reentering information.