A domino effect accident is an accident in which a primary undesired event sequentially or simultaneously triggers one or more secondary undesired events in nearby equipment or facilities, leading to secondary accidents more severe than the primary event.[1] Thus, a domino effect accident is actually a chain of multiple events, which can be likened to a falling row of dominoes. The term knock-on accident is also used.[2]
Domino effect accidents are an important process safety issue affecting process plants where significant amounts of hazardous materials are stored, transported, and processed. Losses of containment that result in fires or explosions can escalate to nearby equipment, due to thermal radiation, blast overpressure or other mechanisms, thus potentially causing further fires, explosions, or toxic gas clouds.[3]