Conducting an Accident Investigation
Course 102
Safety Certified Supervisor Series

MODULE 4: ANALYZING THE ACCIDENT PROCESS

Why accidents happen

The Domino Theory

This explanation describes an accident as a series of related occurrences which lead to a final event that results in injury or illness. Like dominoes, stacked in a row, the first domino falling sets off a chain reaction of related events that result in an injury or illness.

The accident investigator will assume that by eliminating any one of those actions or events, the chain will be broken and future accidents prevented. In the example above, the investigator may recommend removing the sharp edge of the work surface (an engineering control) to prevent any future injuries.

This explanation still ignores important underlying system weaknesses or root causes for accidents.