Accident Analysis - finding causes of unwanted events

Analysis of accidents, incidents and other type of unwanted events is directed at finding the causes that have lead to the event and its consequences.

Accident analysis would normally be directed at three levels:

• direct causes
• basic causes
• management system aspects

Basis causes and management system aspects can be considered the "root causes" of unwanted events. Root causes are at the practical end of the causes analyses; "practical" meaning that the causes can (still) be controlled through efforts and resources that are in proportion to the expected or desired results.

Cause Analysis

When considering cause analysis consider two routes:

• from the event "upstream" to uncover why the event took place
• from the event "downstream" to find out why the losses were as large or small as they were

The investigation protocol shall determine when a cause analysis shall be carried out, depending on the level of risk classification. When establishing the risk level, consider circumstances that are (slightly) different from those of the actual accident, incident or event. Could the consequences of the event be much greater under different circumstances? Consider issues like: if the fire would have occurred during another time of the year, would the loss have been much greater? Or if the fire brigade could not reach your plant in time because there was an accident blocking the road, what would have been the consequences?  Or: if for, whatever reason, there would not be enough water to extinguish the fire, what then?  

Preferably these analyses should be done using a team approach under the guidance of a "facilitator" with sufficient knowledge and expertise of the analysis method being used. The role of this person is of particular importance if the analysis data will be put in a data base for future use and retrieval of information.

Event Cause Analysis

Systems used for cause analyses may include: SCAT (Systematic Cause Analysis Technique) or BSCAT; MORT (Management Oversight and Risk Tree); Causal tree ("Arbre des Causes") or others. Systems and related software can be found using the Internet and appropriate search key words. 

Unwanted event analysis can be an important source of information to improve the management system and all related aspects influencing on the culture of the organization. 

Extent of Loss Analysis ("downstream analysis")

The extent of loss analysis should consider:

• presence and efficiency of barriers between the event and the resulting loss
• the availability of private and public emergency means
• the presence of an up-to-date post event plan (PEP) to limit commercial losses 

Remedial actions ("upstream analysis")

Cause related remedial actions should be developed through a team approach. The following people should be included when selecting team participants :

• relevant management and supervision
• people from department where the event took place
• people carrying out the activities that took place prior to or during the event
• staff people from maintenance, human resources and other relevant departments
• people involved in emergency actions
• facilitator to guide the process of remedial action development

Consider evaluation of effectiveness of remedial actions, before carrying them out as well as after.

To make sure that remedial actions will be carried our properly and in time, consider the following functions:

• event coordinator - person responsible for everything that is related to the accident, incident or event, including the actions to be taken
• action owner - person responsible to assure that the action is carried out properly an in time. This could be the person who actually carries out the action or a person who makes sure that somebody else, possibly outside the company or organization, carries out the work.