AbstractProcess hazard analyses (PHAs) usually focus on major hazards—fires, explosions, and toxic releases. Traditional PHA methods, such as the Hazard and Operability (HAZOP) study and What‐If analysis, often include scenarios for other hazard types, such as operability problems. Sometimes, this may be desired, but not always. There is a need for a PHA technique that directly and exclusively addresses major process hazards. Such hazards are realized when process containment is lost. Therefore, the method proposed here uses a categorization scheme to guide brainstorming of initiating events that can result in fires, explosions, or toxic releases. It provides a more efficient and, likely, more complete, identification of major hazard scenarios than current PHA methods.