Incident Investigations, Policies, and Analysis Practice Test

In incident analysis, an unsafe act is something a person does (or fails to do) that increases risk. Failing to follow instructions or procedures fits this because it reflects a direct action (or inaction) that bypasses established guidance, creating the chance for error or harm to occur. The other items describe conditions or outcomes rather than actions: poor illumination is an environmental hazard, a condition in the workplace; poor housekeeping is another environmental hazard caused by the layout and cleanliness of the area; being struck by debris is the injury or event that results, not an action someone performed. So the unsafe act in the list is failing to follow instructions or procedures.