Root cause investigations—performed properly—can not only prevent recurrence, they may also reveal subrogation claims.

The scopes of work involved in the construction industry present potential hazards that can result in various types of accidents—employee injuries, subcontractor and supplier injuries, heavy equipment and machinery incidents, property damage and bodily injury to third parties. When an accident occurs, everyone wants to know “what happened.” This is often fairly clear cut. However, “why it happened” can be much more challenging to answer. The concept of root cause investigations is about getting to the underlying reasons of why an accident occurred.

Construction workers on a jobsite
I recently conducted an accident investigation workshop for a group of contractor safety management personnel. We reviewed details about an accident involving an employee whose hand was seriously injured in a lightweight portable concrete mixer. “What happened” was clear: the employee reached into a running mixer in order to remove chunks of materials that had dried and accumulated. “Why it happened” was a different story and one that takes a lot of time and effort to fully investigate and understand.

In the case of any serious accident, there is often a chain of events, or “error chain,” that led to the incident. Every link in the error chain needs to be carefully investigated in order to accomplish what would be considered a thorough root cause analysis. Until an investigation identifies the root causes of an accident, you cannot get to the critical point of why you are even conducting the investigation—to prevent the accident from happening again.

One of the most important reasons to conduct a detailed root cause analysis is to identify all factors that may have contributed to the accident and determine solutions and actions to prevent recurrence. If all the contributing factors are not identified and action plans are not implemented to address each factor, the likelihood of the same or a similar incident occurring still exists.

Subrogation Claims
Another important reason for detailed root cause investigations is the possibility of “subrogation” actions against other entities or parties that could have contributed to the event. The term “subrogation” refers to the act of one person or party standing in the place of another. Subrogation issues often surface when an employee has been injured and someone other than the person or party at fault pays for all or some of the damages resulting from the injury.

A subrogation claim permits the innocent paying party, often a self-insured employer or an insurer, to stand in the place of the injured person. The employer and insurer work together to address the immediate needs of the injured employee, acting on behalf of the injured. Ultimately, the reason an employer or insurer would then be interested in the root cause of an accident is to determine whether a third party is responsible for paying for all or some of the damages resulting from the injury. If other parties are found to have contributed to the accident, a subrogation action against that third party may occur, along with possible recovery of all or part of the dollars paid to care for the injured employee.

A Case Study
Using the concrete mixer accident as an illustration of subrogation potential, we see that an employee was seriously injured in the course and scope of employment, and therefore a workers’ compensation claim was set up to handle the medical bills, expenses and possible indemnity (percentage of lost wages) that the employee incurred while off work.

The workers’ compensation claim is immediately set up regardless of the results of the root cause analysis, as a means to ensure that the injured employee is properly cared for. At this point in the claim process, the focus is not on whose fault the accident was or who else could have contributed to the accident but rather the employee’s medical care, expenses and potential lost wages, which comprise the total claim dollars associated with the accident.

Once these immediate needs are taken care of, the focus of the claim investigation often turns to understanding the details of the accident and the results of the investigation. The internal accident investigation conducted by the employer involved in the mixer accident identified the following issues as potential causes of the accident, all of which were legitimate and involved corrective actions that could be implemented immediately:


  • The injured employee had been working for the company for only two weeks and had not received a full safety orientation or training on that type of equipment.
  • The required pre-task hazard analysis for the concrete operations taking place the day of the accident had not been completed by the supervisor and was not discussed in the daily meeting.
  • The supervisor was not present in the work area at the time of the accident, and the employee had never used that type of mixer before.
  • The injured employee had no reason to place his hand into a running mixer.

These types of causes are often identified in construction accident investigations. However, what was missed in this investigation was an identification of the root causes of these four inadequacies.

Digging Deeper
You will also notice that none of these determined causes have anything to do with a third party—only with the employer and employee. We selected this specific accident for an accident investigation workshop to determine whether anything was potentially missed in the original investigation. As the group discussion ensued and various questions were asked to dig further into root causes, we identified issues that had not been considered.

First, there was a defective switch that engaged the mixer blades. It appeared to have been replaced recently and would not stay in the on or off position without manual assistance. Additionally, an interlock was supposed to be in place that would shut down the mixer blade when the mesh screen was lifted to access the mixing drum blades.

These two discoveries highlight other factors that led to specific actions that were taken to investigate subrogation potential. It turned out that the mixer had recently been serviced by a third-party maintenance firm. The original interlock device that came with the equipment was no longer available, so it was replaced with a switch from a different model that did not function properly on this mixer. Although these items were not the sole reason for the accident, there was enough evidence to illustrate that had the switch and interlock been properly functioning, the mixer blades would not have continued rotating once the screen was lifted.

In the chain of events that led to this injury, there were errors made by the employee and employer; however, there were also contributory errors made by a third party. In this case, the third party was found to be culpable for at least a portion of the injury damages, and the employer and insurer were able to recover a percentage of the total dollars paid on the claim.


Once the root causes for any accident have been fully identified, the efforts made to correct identified gaps and prevent recurrence of such accidents will be more successful. As far as insurance matters are concerned, the root cause analysis process is also critical to identifying all potential avenues of subrogation, which will have a direct positive impact on the bottom line of the contractor when recoveries from culpable third parties can take place. It is important to continually assess the accident investigation process in place at your company and tap into the resources you have available from your insurance partners for gap analysis, process/procedure development and supervisory training. 

Disclaimer: Information, comments or ideas that are presented herein are for general educational and informational purposes only, and do not constitute a solicitation to buy insurance. Neither the author nor Arch Insurance Group represents or warrants that the information contained here is complete or accurate. Nothing presented herein is intended to, nor shall be construed to, interpret, modify, alter or amend any terms or conditions of any contracts or policies of insurance that have been or may be issued by any insurance company within the Arch Insurance Group and the terms and conditions of such contracts shall be controlling. The views expressed herein are solely those of the author and do not necessarily reflect the views of Arch Insurance Group. The information contained herein is not to be construed as legal advice or opinion.