“Incident investigation is like peeling an onion. Beneath one layer of causes there are other layers. The outer layers deal with the immediate causes while the inner layers are concerned with the underlying causes such as weakness in the management system.”
Trevor Kletz – Learning from Incidents in Industry
The immediate causes are normally the easiest to ascertain, and it is essential to establish these to determine any underlying causes. They provide a starting point for the investigation. The immediate causes will be the details immediately provided by people, positions and parts. There will usually be tangible evidence.
Most of the immediate causes will be established in the early stages of the investigation when the investigator is gathering preliminary information, taking photographs, identifying witnesses and what they can contribute to the investigation. The information will be gathered from people, position and parts. Paperwork invariably will not provide information on the immediate cause of incidents.
Witnesses will provide most of the detail of the immediate causes with minimal prompting or questioning, particularly when they are interviewed within a close time frame to the event. Some prompting may be necessary to obtain confirmation of points raised by another witness. However, it is essential that the investigator avoids leading the witness.
The Certificate IV in OHS unit – Participate in the Investigation of Incidents – will assist you in analysing workplace accidents and incidents.