The accident investigation is an important component of occupational health and safety programs, and an essential part of building a successful workplace safety culture. This overview of accident investigations is general in nature, designed to provide an overview of the process regardless of jurisdiction.
Reasons to perform accident investigations often include:
- Fulfillment of legal requirements
- Assessing compliance with established safety procedures
- Prevention of future accidents of a similar nature
- Enabling the processing of worker’s compensation claims
- Demonstrating concern about employee well being
Taking a step back, an accident can be described as an unintended event that results in injury or property damage. An incident can be described as an unintended event that does not result in injury or property damage. Additionally, hazard can be described as the potential to do harm, while risk is defined as the likelihood of harm actually occurring. Other terms such as “Near miss” are used to describe incidents that could have easily ended up being serious accidents. Some jurisdictions avoid the use of the term "accident", because the latter term infers that the event could not have been avoided. They choose to use “incident” instead, pointing out that most events are predictable and preventable. To the extent that the risk is managed, there is less chance of an accident occurring. The depth of the investigation should be appropriate to the seriousness of the situation in terms of actual or potential injury.
Looking to Determine Root Cause
In the past, accident investigations have typically focused on assigning blame rather than finding the underlying root cause, which if addressed, can reduce the likelihood of a similar accident in the future.
Choosing an Investigation Team
The investigation should be conducted by someone who is familiar with the workplace, as well as having someone who has been trained in the accident investigation process. Typically, the immediate supervisor is involved, although the level of management participation will be often influenced by the seriousness of the accident. The more serious the accident, the more likely that senior managers will participate. Worker participation also aids in effective investigation. Such workers should be familiar with the work being done. These often include, but are not limited to the health and safety representative, union representative or others. In addition, outside experts may be called upon to participate. Investigations are strengthened by the perspectives of others who are knowledgeable about the workplace and investigation procedures.
The Accident Investigation Process
The accident investigation process includes six important steps. These include:
- Investigation of the accident
- Identification of direct and root causes
- Disclosure of findings
- Development of a corrective action plan
- Follow-up review and revision as necessary
In order to perform a proper initial investigation, it should take place as soon as possible after accident. General supplies useful to the investigator will include such items as a camera, barrier tape measure, flashlight, paper, incident investigation form and pencil. The initial investigation will involve securing the scene as much as possible after aiding the injured worker, recording physical evidence, and then interviewing workers.
The Six W’s is one simple but proven methodology that helps field investigators build a solid understanding of the event:
- Who is it about?
- What happened?
- Where did it take place?
- When did it take place?
- Why did it happen?
- How did it happen?
Discovering Immediate and Root Causes
The workplace factors are assessed to see if they have been contributing factors. Such factors include:
- People factors
- Material factors
- Environmental factors
- Management system factors
- Work/Process Task factors
In determining the cause of an accident, it is often easier to identify the immediate cause rather than the root cause. With this in mind, one commonly used approach is to employ the Three Why’s technique. For example, the immediate cause of an employee slipping may be due to a wet floor (why did the employee get hurt). The next why may be “Why was the floor wet.” When finding out that the organic recycling bin is leaking fluid, the next question may be “Why is the bin leaking?” Through such process the recommendation of the committee may be to repair or replace bins so that they do not leak. Additionally, investigators may recommend temporary measures to reduce risk until the bins are replaced – perhaps relocating the bins. Another recommendation might be for a scheduled inspection of bins to make sure that they are not leaking.
While this has been a fairly simple illustration, techniques such as the Six W’s and the Three Why’s can be used to investigate many accidents in conjunction with the basic investigative steps outlined above.
Accident Investigation Resources
Two helpful resources for accident investigation include OSHA and the WorkSafe Alberta Incident Investigation Guide.
In some respects, the Accident Investigation is a bit like driving in the rear view mirror, in that the negative outcome has already taken place, rather than proactive programs such as promoting safe equipment operation. As part of your safety program, however, it enables you to correct deficiencies and thereby recurrences of similar accidents in the future.