How to Conduct a Workplace Accident Investigation

Since 1971, OSHA (Occupational Safety and Health Administration) has aimed to ensure safe working conditions by setting and enforcing thousands of safety standards. And in a perfect world, there would be no workplace incidents or work-related injuries. However, all the safety regulations and best practices in the world cannot guarantee total employee health. Most companies will find themselves faced with a workplace safety issue at some point, whether it be a minor injury or a major disaster. And when that happens, it’s important for anyone involved to understand the next steps. Training your entire workforce on incident management is wise because you never know who will be involved in workplace incidents, and therefore who might need to initiate action. Keep reading to discover workplace accident investigation procedures and things to keep in mind, plus learn more about investing workplace accidents from HSI.

How would you go about investigating this tragedy?

In this case, the company employed only four workers along with the two co-owners. There was no full-time or part-time safety and health professional involved. In operations staffed with a safety professional, the pro would have already assembled a team to investigate incidents, readied for situations like this one. This small team (easier to manage), headed by the pro and including perhaps two workers and hopefully at least one supervisor and a manager, would be trained in conducting investigations and ready to go as soon as an incident occurred.

The team, if it had been involved, would begin its work by reviewing photographs of the incident site and witness statements taken by the Occupational Safety & Health Administration (OSHA). The state police report, medical examiner’s report, and the death certificate would be reviewed. The team would learn that the victim was the only minor working for the company. This she did as a summer job. She was hired because she was a friend’s relative.

The investigative team would continue to collect information on the victim, her job history, and her most current job duties. She loaded construction materials into a truck for transport to a jobsite and assisted with loading materials purchased at a lumberyard. The president of the company, when interviewed, said this was the second summer the victim had worked for his company, and on approximately ten occasions she had worked on roofs. At the time of the incident, the victim wore a tee shirt, dungaree shorts, and work boots.

Further interviews and research discovered that the company did not have any kind of written safety program, and that workers did not receive any safety training.

Investigators studied and filmed the incident scene. The fatality occurred at a residential Victorian-style house that had been converted into a six-unit apartment building. The owner of the building had hired the roofing contractor to remove old roofing shingles and install a new roof. The building was a three-story structure, 26 feet in height and with a 12 pitch roof. The construction contractor had placed two wooden planks secured with roof brackets on the rear portion of the roof.

Weather conditions were also checked. It was sunny and partly overcast, and at the time of the incident the temperature was in the 80s. The investigative team next constructed a timeline of events, beginning at 7:00 am on the day of the incident when the roofers, including the victim, arrived at the house to begin work. Interviews with those on site where the incident occurred are really the only way to collect reliable information. It’s important to remember the people being quizzed have been traumatized by the incident, are likely in a highly emotional state, and often automatically defensive. Investigators cannot conduct these tense, emotional interviews without training.

Training must be a mandatory prerequisite. This was everyone’s second day working at this site. As they began work, the owners verbally reminded the male laborer and the victim to be careful while working.

A construction box was used to haul down used roofing shingles and to bring construction tools and supplies up to the roof. The homemade construction box was attached to the forks of a forklift. The owners or the male laborer would move the forklift with the construction box attached and relocate it near the area where the roof work was being done. The victim would use a ladder to climb up onto the roof, and then she would throw trash and used roofing shingles into the construction box. When new roofing shingles were needed on the roof, the construction box would be lowered to the ground and the victim would load the bales of roofing shingles into the box.

At about 2:15 pm, the victim was observed sitting on one of the two installed wooden planks on the roof. No one actually saw her slip and fall.

What Is the Point of Incident Investigations?

Many workplace incidents have both root and surface causes. The root cause of the accident might be a weakness in a work process or a management practice that directly contributed to the incident, while surface causes are the immediate causes of workplace incidents, such as unsafe behaviors by the worker or unsafe conditions in the work area.

Both the root cause of the incident and the surface causes should be determined with a thorough investigation and corrected. If a work-related accident occurs and you only correct the surface causes, similar incidents could occur again.

How to Conduct Incident Investigations

Too many times, safety investigations take the path of least resistance. The employer wants to wrap things up and move on. This usually results in the injured workers being blamed for reckless behavior. In cases that are not fatalities, the recommended resolution to the case is very often more training for the injured workers.

But investigators should step back and take in the entire incident scene, looking for contributing factors. Many incidents are not simple, having multiple causes that need to be mitigated, if future similar accidents are to be avoided.

Implementing a capable and comprehensive accident investigation process is critical in the aftermath of workplace incidents. You not only need to uncover the root cause of the incident but also determine how to prevent similar future incidents.

Here are some critical pieces of workplace incident investigations:

Assign an accident investigation team that includes safety professionals, day-to-day workers, immediate supervisors, and managers. Each of these worker segments is likely familiar with the job in a slightly different way, bringing unique perspectives to the incident investigation process. Don't wait for a work-related accident to build this team — do it now so they are knowledgeable of the accident investigation process.

Conduct investigation training with the assigned team members, both individually and as a group. Regular training includes understanding safety regulations and the accident investigation process, while mock investigations help sharpen the investigative team's skills. The group should have experience in the work being investigated under the direction of safety managers and encourage investigation team members to speak freely about their perceptions of what happened at the time of the incident.

Review of the site and relevant documents are crucial steps in workplace accident investigations. Events can move quickly after workplace incidents, so it’s important to secure the work area immediately. Even if the incident is minor, avoid disturbing the accident scene and moving physical evidence if possible. The incident site includes the environmental conditions of the work area, tools or equipment used, physical evidence, and potential safety hazards. OSHA reports, company and employee safety records, and maintenance logs give the investigation more context.

Gather witness statements and understand how to do so in an empathetic, respectful way. Witnesses are more willing to help when they don't feel like they are being investigated. Remember, they may have witnessed something traumatic! And be sure to seek out witnesses in different roles whenever possible, as diverse perspectives add additional insight. Document your interviews in official witness accounts, focusing on facts and witness observations vs. interpretations.

Conducting a factual analysis and distinguishing facts from assumptions ensures the incident investigation process is upheld in an objective and unbiased way. Identifying the contributing factors, and ultimately the root cause of the incident, allows you to prevent future similar incidents.

The bottom line: workplace accident investigations must be conducted fairly and with an open mind by everyone who is part of the investigation, with no preconceived notions of what might have happened.

Implement a Corrective Action or Preventive Action Plan

Once you have identified the root cause of the accident you are investigating, you’re ready to determine the corrective and preventive actions (CAPAs) needed to try and keep similar future incidents from happening. After all, if all the investigation does is tell workers they need to be more careful, it won’t solve the issues that caused the incident in the first place.

A corrective action is reactive and is intended to fix the safety hazards in question. For instance, if an overhead crane falls because an old chain breaks, you replace the chain.

Preventive actions are proactive to ensure the incident, or similar incidents, don’t happen in the future. In our example, you could create a standard operating procedure to inspect all chains in the facility at regular intervals.

Of course, the specific action plan you implement will be based on your specific needs, but CAPAs will fall within the hierarchy of hazard control. Here is a breakdown of the hierarchy of hazard controls, from most effective to least effective:

• Elimination consists of physically removing the safety hazards. For instance, if employees are working high above the ground, move the piece they are working on to ground level.
• Substitution replaces something that produces a hazard with something that does not. A common example is the use of titanium dioxide instead of lead-based paint.
• Engineering controls isolate people from hazardous conditions in the work area but do not eliminate the hazards themselves, such as adding guard rails rather than investing in fall arrest systems.
• Administrative controls change how people work to limit exposure to hazards. This ranges from installing warning signs throughout the work area to implementing procedural changes.
• Personal protective equipment (PPE) reduces exposure to hazards when engineering and administrative controls are not feasible or effective. PPE is needed whenever there are safety hazards present.

Despite being at the bottom of this hierarchy, personal protective equipment is often much easier to implement than other controls, and various types of PPE can be easily used in any work area.

The Next Step After a Thorough Investigation

Perhaps the most important step of the incident investigation process is what comes after. The findings of safety investigations require action. Safety procedures, or even the work area, are often what need to change, not the injured employee.

Once you have completed a thorough investigation, identified what went wrong, and put together an action plan for the future, be sure you communicate your findings and decisions. After all, if not everyone is aware of a corrective action or preventive action put in place, there is still a risk of future occurrences of the incident. A thorough investigation is a complete waste of time if recommendations to prevent future incidents are ignored.

While so much of the occupational health and safety industry is about being proactive and recognizing — and then hopefully eliminating — safety hazards before they can even become an issue, a work-related accident can still happen. And when it does, everyone needs to be prepared with an accident investigation plan.

Most workplace incidents can be avoided, but it’s important for your company to have an investigation plan in place if an incident does occur. By conducting a thorough investigation and using the information you find to correct safety hazards in your workplace, you can help prevent similar incidents from occurring again.

For more than 40 years, HSI has worked to incorporate important occupational safety topics into more than 800 mobile-friendly, interactive training courses.

See how HSI can help you create an intuitive, functional, and effective outcome-based safety program that can help you maintain the relevant documents for a thorough investigation, take steps toward preventing future incidents, implement engaging safety training, and much more.