Which regulation defines the occurance of an action or situation as a serious incident that may have important or dangerous results?

The regulation that defines the occurrence of an action or situation as a serious incident is typically found within safety and health regulations, such as those outlined by the Occupational Safety and Health Administration (OSHA) in the United States or similar bodies in other countries. These regulations specify criteria for serious incidents, emphasizing potential hazards that could result in significant injury, illness, or environmental harm. Additionally, in aviation, the International Civil Aviation Organization (ICAO) defines serious incidents in its Annexes regarding safety management.