Frank Crawley is a seasoned Chemical Engineer with over 40 years of experience in the chemical and oil industries. He began his career in Olefine Plants and specialized in Nylon Intermediates following the Flixborough Explosion. Frank led the Loss Prevention group at a major oil company and has over a decade of consultancy in the offshore oil sector. He has published over 50 refereed technical papers and received the IChemE Franklin Medal for teaching safety. As a co-author of the "HAZOP Guide to Best Practice," Frank is recognized for his significant contributions to chemical engineering safety. Brian Tyler co-founded his consulting company with Bob Simmons in 1990 while also working at the University of Manchester Institute of Science and Technology (UMIST). With over 20 years of experience in organizing safety courses in the chemical industry, he focused on topics such as HAZOP, fire and explosion, and accident investigation. His course "HAZOP Study for Team Leaders and Team Members" continues to be offered by IChemE. Brian co-authored two IChemE monographs, "HAZOP: Guide to Best Practice" and "Hazard Identification Methods." In 2011, he became one of the first Associate Fellows of the Institution of Chemical Engineers.