Paul Anastas, the Yale chemist widely credited as a founder of green chemistry, traces the history of major chemical accidents and asks what safer industrial design could have prevented. Part of Module 10 in his course Introduction to Green Chemistry, the talk moves through case studies of past disasters to show how hazard is not an unavoidable cost of chemical manufacturing but a design failure that can be engineered out from the start. Anastas connects specific accident histories to concrete principles of green chemistry, arguing for building safety into molecular and process design rather than relying on containment or regulation after the fact. The module is brief and focused, aimed at students already following the course's broader framework for reducing hazard and waste in chemical systems.