
When an accident occurs at your facility and an employee gets hurt, a quick assessment of the situation might find the employee wasn’t wearing proper PPE or wasn’t following procedures. This could lead accident investigators to conclude that the employee in question needs to be reminded about complying with safety policies.
While 95 percent of workplace accidents are the result of unsafe behaviors, according to OSHAcademy, an organization that provides training courses, those unsafe behaviors are surface causes. Surface causes like unsafe behaviors and hazardous conditions in the workplace do contribute to accidents, but they are often the result of underlying causes, called root causes. These root causes are usually systemic problems such as inadequate safety policies or enforcement of policies.
For example, an accident involving an employee not wearing appropriate PPE like eyewear may not be as simple as it appears. If the investigators dig a little deeper, they may find the reason the employee wasn’t wearing eyewear was because his goggles didn’t fit properly, which impaired his ability to do his job. Then the solution to the problem isn’t simply reminding the employee what to do. The company must instead assess whether they are providing appropriate PPE and whether they need to switch models of eyewear or do a fitting for each employee to make sure the gear will work for everyone. In this case, simply blaming the employee doesn’t solve the problem at all.
Root cause analysis, then, is simply the process of taking the time to thoroughly investigate workplace accidents and other problems by asking why an event happened the way it did.
Investigating Accidents to Determine Root Causes

Some workplaces provide forms for investigators to fill out detailing what happened prior, during and after an accident. These forms can often be helpful, but in some cases they limit the thinking of those involved in the process. A form may not list all the questions that need to be asked during an investigation and all the factors that need to be considered. If your company uses forms, make sure they help the process rather than hinder it.
Forms aside, what does a business need to do after an accident or near miss in the workplace occurs? The most important thing is to gather the needed people and materials and get to work right away, according to the Canadian Centre for Occupational Health and Safety (CCOHS). Critical information and evidence can be lost if you don’t act quickly.
Who is involved in investigating an accident will depend on the situation, but in general, those knowledgeable about the work being done should participate. Managers and safety managers are important, and if your company has a health and safety committee, its members could be involved, too. This team should gather data from the accident scene about conditions in the workplace (weather, temperature, tasks being performed, machinery being used, etc.) and employees involved (interviews should be conducted). Once all information has been gathered, it’s time to begin assessing what really caused the accident.
Issues to Explore

In the majority of accidents, there is more than one contributing cause. Consequently, investigators should ask questions about the following five topics:
- Task – Consider the work procedure itself. Were proper procedures followed? Was the normal procedure unsafe for some reason? Were proper PPE and tools used?
- Material – Consider the machines, chemicals and other equipment involved. Did something fail? Were hazards identified for workers?
- Environment – Consider the surroundings. Were lighting or noise a problem? Was the weather unusual?
- Personnel – Consider the employees. CCOHS emphasizes the importance of not blaming employees. You should ask plenty of questions about employees, though. Were they properly trained? Were they stressed or ill?
- Management – Consider whether management of the safety system played a role. For example, did supervisors communicate instructions clearly? Did they inspect machinery regularly?
In all of these areas, if something contributed to the problem, ask why that issue is the way it is. This practice is sometimes referred to as “The Five Whys,” which basically means you should keep asking why something is true until you have found a root cause for a problem. In our opening example about an employee not wearing eyewear, investigators could ask a series of questions like this:
Why did this employee not wear eyewear? Because it did not fit him properly and he felt it impeded his ability to do his job.
Why did his eyewear not fit? Because the company only provides one kind of eyewear and did not do fit testing for every employee.
Why doesn’t the company provide more than one style of eyewear? Because it was determined to be too costly.
The root of this problem is the limited eyewear selection, not the employee who chose not to wear his PPE. In this case, the company would need to reevaluate its PPE program to determine whether an expanded eyewear selection should be made a priority.
To help you visualize the process of seeking out root causes, OSHAcademy offers a helpful graphic about getting to the bottom of accident causes.
OSHA Recommendations for Root Cause Analysis
It’s obviously important to investigate accidents as soon as possible to find out what happened and determine root causes. Doing so can help uncover underlying problems in a safety system, and fixing those problems could help prevent future accidents.

OSHA also suggests doing periodic audits of accidents and near misses to determine if there are any patterns. A company could do this by examining its annual OSHA 200 form, which is a summary of occupational injuries and illnesses from that year.
By taking a closer look at all the problems from a given year, employers and safety managers may discover that the most common type of injury at the company involved lower back strain from lifting or eye injuries from flying debris around power tools. By looking at the bigger picture and not just an isolated incident, it may be easier to determine whether causes like employee noncompliance with safety procedures, improperly communicated procedures or an inadequate PPE program are to blame. Then the company can take steps to adjust the safety system for the future.
Keep in mind, though, that detailed investigations and asking thorough questions when an incident occurs will make an audit at the end of the year much more effective.
Don’t Assume
Root cause analysis isn’t a complex practice, but it does require diligence. It’s easy to assume you know right away what caused an accident. Unless you ask the right questions, though—and keep asking them—you may just be putting a Band-Aid over a problem that is much deeper than it seems.
Unsafe behaviors do cause many accidents, but employees for the most part aren’t ignoring safety procedures because they are lazy or don’t care about safety. In most cases, there are reasons—many of them legitimate—that unsafe behaviors and conditions exist, and it’s your job to figure out what those root causes are. Once you do, you’ll be on your way to creating a more effective safety system.
Additional Resources
- The Five Whys (Root Cause Analysis)– creativesafetysupply.com
- Accident Investigation – Everything You Need to Know About Surviving A Post-Accident Investigation– blog.creativesafetysupply.com
- Why Six Sigma Root Cause Analysis is a Great Tool– kaizen-news.com
- The Great Root Cause Problem Solving Debate– realsafety.org
- Accident Prevention in the Workplace– safetyblognews.com
- JSA – Job Safety Analysis Explained– aislemarking.com
- Using Accountability to Drive Safety– blog.5stoday.com
- Permit-Required Confined Spaces – Do You Know What They Are?– babelplex.com
- How can Lean affect safety?– hiplogic.com