A notifiable occurrence is an unplanned event or situation that can cause injury, illness, damage or loss. A person conducting a business or undertaking (PCBU), including the operator of a facility, should first assess a situation to determine if a notifiable incident or notifiable occurrence has taken place.

In addition to reporting notifiable incidents, petroleum and geothermal operations must also report notifiable occurrences.

Notifiable occurrences and a list of additional dangerous incidents are defined in the Work Health and Safety (Petroleum and Geothermal Energy Operations) Regulations 2022.

Notifiable occurrences include the following:

• an occurrence that did not cause, but could reasonably have been expected to cause:
  • the death of or serious personal injury to a person
  • a worker to be incapacitated from work for a period of 3 or more days
• the failure of a safety critical element (SCE) to meet the requirements of the performance standard. An SCE is a part of a system or equipment essential for preventing or mitigating major accidents (e.g. a fire suppression system on an offshore oil rig fails to activate during a fire leading to a catastrophic fire, endangering lives and causing significant damage)
• the defect of or damage to a safety critical element
• the significant defect of or damage to a primary petroleum containment
• the significant defect of or damage to a structure, marine vessel or item of plant that forms part of an industrial, chemical or physical process performed on:

• petroleum
• fluid containing geothermal energy 
• a well kick (unwanted influx of formation fluids such as gas, oil, or water into a wellbore) that requires immediate action to be brought under control
• an event that requires the emergency response plan to be implemented
• in relation to diving activities:
• a decompression illness
• a pulmonary barotrauma (a type of lung injury that occurs when there is a sudden change in air pressure, causing damage to the lung tissue)
• a case of inadequate or lack of decompression
• an occurrence for which the standby diver is deployed for an emergency, except for the purposes of training, exercises or drills
• a failure of life support equipment or man riding equipment (specialised devices and systems designed to safely lift, lower and transport personnel in various work environments. Commonly used in industries such as construction, mining, and offshore drilling)
• any other event that a reasonable operator would think needs immediate investigation.