When it comes to incident investigations, depth matters

Credit: Adobe Stock/ipuwadol.

Incident investigations are a critical process for any organization to identify the root causes of incidents, near misses, or other undesired events. They often reveal weaknesses in existing safety systems, protocols, training, or equipment.

However, if an investigation is done poorly, incompletely or lightly, it can be counterproductive and leave deficiencies unaddressed. It is important that only competent personnel conduct incident investigations.

Doing a proper investigation requires the investigator to look into the facts of the incident beyond the superficial details. It’s easy to blame the worker and then make the corrective action to “discuss in the safety meeting” but this doesn’t address the real causes or contributing factors and won’t prevent the incident from occurring again. Unfortunately, investigations are often completed without drilling down into why an incident occurred in the first place, leading to superficial findings. This may be due to lack of investigator experience or training, time pressure to get an investigation report out, or reluctance to expose greater system faults in the organization.

So, if the incident that occurred involved the following details, what levels of investigation depth might we see from subsequent reports?

A worker was walking down the administrative building east hallway, travelling north towards the warehouse, when they slipped and fell, spraining their wrist.

Levels of investigation depth

1. Superficial investigation (blaming the worker)
   • Findings: “The worker wasn’t paying attention.”
   • Action: Discipline or retrain the worker.
   • Problem: Ignores deeper issues, meaning the same incident could happen again.
2. Basic investigation (looking at immediate causes)
   • Findings: “The worker slipped on a wet floor.”
   • Action: Clean up spills faster and put up signs.
   • Problem: Doesn’t examine why spills happen or why signs were not present.
3. Deeper investigation (examining contributing factors)
   • Findings: “The floor was wet because of a leak that was reported but not fixed.”
   • Action: Improve maintenance response times and ensure hazard reporting is effective and followed up on.
   • Problem: This approach still might not address cultural or systemic issues.
4. Root cause investigation (systems thinking)
   • Findings: “Leaks were a recurring issue because maintenance was understaffed, and work orders were deprioritized by management.”
   • Action: Increase maintenance resources and review safety prioritization in decision-making.
   • Benefit: Prevents future incidents by addressing the underlying system failures.

Techniques to help investigators dig deep

All investigations should follow the process of securing the scene, collecting evidence, conducting interviews, and creating a timeline. Investigation techniques may differ in the methodology for determining causes, but the fundamental concept of determining causes is the same.

Various methodologies may differ in their approach and tools for causal analysis in an investigation. Here are some examples:

1. The Five Whys

The Five Whys is a problem-solving technique used to explore the root cause of an issue by asking “why” five times in succession. Each “why” digs deeper into the reasons behind a problem, gradually revealing its underlying causes.

2. Systemic cause analysis technique (SCAT)

SCAT is a widely used methodology for structured analysis of incidents. SCAT looks at predefined categories of loss events, starting with the loss and working backward to the event, then ending with causes and control measures to minimize the recurrence of the event. Investigators can select from a chart that provides event types, immediate/direct and basic/underlying causes, and lack of control measures that are related to the incident.

3. TapRooT (techniques for human error reduction and root cause analysis)

TapRooT is a systematic process for investigating incidents, identifying root causes and implementing effective corrective actions. It involves a structured approach to gather and analyze information about an incident, including what happened, why it happened and what can be done to prevent recurrence. TapRooT uses a series of tools and techniques, including the SnapCharT (sequence of events), Root Cause Tree, and Corrective Action Helper, to guide investigators through the analysis process.

4. Cause Mapping (method of root cause analysis)

The Think Reliability Cause Mapping method is a structured, visual approach to root cause analysis that focuses on identifying and understanding cause-and-effect relationships in problem investigations. It uses a simple “why” questioning technique to break down complex issues into a logical flowchart, helping organizations pinpoint the root causes of failures rather than just symptoms.

These are just a few examples of incident investigation methods; there are many other approaches and tools available, including the analysis of human factors that may have contributed to an event, such as fatigue, workloads, miscommunications, or cognitive biases. The choice of method depends on factors such as the nature of the incident, the complexity of the investigation, and the preferences and expertise of the investigation team.

Nicole Orr is chief operating officer of National Safety Services. Carol Casey, CRSP, NCSO, GSC, is an HSE specialist at National Safety Services.

• Tweet

• Psychological health and safety series #3: Creating an effective workplace psychological health and safety policy
• The bus has left the station: Why employers must address psychological health and safety