How to Conduct Fatigue-Focused Incident Investigations & Enhance Workplace Safety

Safety incidents are an unfortunate reality in many workplaces, but what often goes underreported are the hidden causes behind these events—fatigue being one of the most significant. Fatigue affects cognitive function, physical performance, and decision-making, all of which can contribute to safety incidents. Conducting a thorough incident investigation that takes fatigue into account is essential for identifying the root causes of safety issues and improving the safety culture within your organization.

In this article, we’ll explore how to conduct a fatigue-focused incident investigation, uncovering the role fatigue plays in workplace incidents and the steps you can take to enhance your organization’s safety and reduce risk.

Why Fatigue Matters in Incident Investigation

Fatigue is often a silent contributor to workplace safety incidents, and many organizations fail to identify it during investigations. Understanding fatigue's impact on worker performance is key to reducing risk and preventing future accidents. Human fatigue can impair decision-making, decrease focus, slow reaction time, and lead to physical and cognitive errors, all of which are risk factors for incidents in any workplace, from manufacturing floors to transportation to office environments.

Despite its serious consequences, fatigue is often underreported for several reasons, including:

• Self-reporting issues: Employees may be reluctant to admit to fatigue due to fear of negative consequences such as job loss or disciplinary actions.
• Difficulty in quantifying fatigue: Fatigue is a subjective experience, and there is no one-size-fits-all measurement to gauge its severity or impact.
• Lack of awareness: Both workers and supervisors may not recognize the signs and symptoms of fatigue.
• Adrenaline masking fatigue: The adrenaline rush after an incident can sometimes obscure the feelings of tiredness during interviews or investigations.

Understanding the role of fatigue in workplace incidents can help organizations better protect their workers, prevent serious injuries, and avoid costly financial repercussions.

Best Practices for Conducting a Fatigue-Focused Incident Investigation

1 - Evaluate the Circumstances of the Incident

The first step in any incident investigation is to assess the circumstances surrounding the event.

This includes examining factors such as:

• Environmental conditions: Were there any external factors such as weather, poor lighting, noise, or other distractions that may have contributed to the incident?
• Workplace layout and ergonomics: Were there obstacles, poor visibility, or uncomfortable working conditions that could have impacted performance?
• Timing: Was the incident more likely to happen at a time when fatigue typically peaks, such as the end of a shift, after long hours, or during overnight shifts?

This comprehensive evaluation helps rule out other contributing factors and focuses attention on fatigue-related risks.

2 - Interview the Involved Parties About Work Schedules and Fatigue

Interviews are a crucial element of any incident investigation, especially when investigating fatigue-related factors.

In this step, you want to ask detailed questions about:

• Work schedules: Did the individual work long shifts, irregular hours, or back-to-back shifts that could have led to fatigue?
• Job tasks: Were the tasks performed physically or mentally demanding? Fatigue risks are higher with strenuous, repetitive tasks.
• Sleep habits: Did the worker get adequate rest prior to the shift? Did they have any sleep disturbances or personal factors (e.g., family issues, medical conditions) that may have contributed to fatigue?
• Substances: Ask about the use of substances such as caffeine, alcohol, or prescription medication that may impact energy levels and alertness.

Understanding the specifics of the individual's sleep patterns, work hours, and lifestyle factors will help identify whether fatigue was a contributing cause of the incident.

3 - Interview Witnesses for Signs of Fatigue

Witnesses who were present during or before the incident can provide valuable insights into the fatigue of the involved worker.

Ask witnesses:

• If they noticed signs of fatigue such as yawning, slow reaction times, lack of focus, or uncharacteristic mistakes.
• If they recall any previous conversations in which the worker expressed feeling overly tired, stressed, or unable to focus.
• If the worker exhibited signs of sleep deprivation or showed a change in behavior that could indicate fatigue.

Witness testimonies can help confirm whether fatigue was a visible factor leading to the incident.

4 - Review Work Schedules and Job Tasks

A crucial part of any incident investigation is reviewing the work schedules and job tasks that the involved individual was assigned.

This can help identify whether fatigue-related risk factors were present, such as:

• Long hours: Were employees working overtime or extended shifts?
• Shift patterns: Were shifts irregular or poorly aligned with natural circadian rhythms (e.g., rotating shifts, night shifts)?
• Workload: Was the workload disproportionately heavy, contributing to mental or physical exhaustion?

This review helps determine if scheduling practices or job design played a role in increasing fatigue risk, allowing for targeted corrective action.

5 - Examine Policies and Procedures for Fatigue Risk

Many workplaces have policies in place to prevent fatigue-related incidents, but these policies may not always be enforced or may have exceptions that undermine their effectiveness.

During an incident investigation, ask:

• Were there any exceptions made to work hour limitations or rest periods (e.g., extended shifts or reduced break times)?
• Did management prioritize production goals over worker rest or well-being?
• Were there opportunities to adjust staffing levels or restructure shifts to reduce fatigue risks?

By reviewing existing policies and procedures, investigators can determine if improvements or stronger enforcement are necessary to mitigate future fatigue-related incidents.

6 - Develop Recommendations and Corrective Actions

Once fatigue-related causes have been identified, the next step is to implement corrective actions that can prevent similar incidents in the future.

These actions might include:

• Revising work schedules to ensure they align with workers' natural sleep-wake cycles (e.g., designing more biocompatible shift patterns).
• Providing fatigue management training to educate workers and managers about the importance of sleep, healthy lifestyle choices, and how to recognize fatigue symptoms.
• Improving break schedules to ensure workers have adequate time to rest during long shifts, preventing fatigue buildup.
• Creating a Fatigue Risk Management System (FRMS) that includes regular assessments, monitoring, and policies to manage fatigue across the organization.

These corrective actions not only reduce the likelihood of future fatigue-related incidents but also show a commitment to worker safety and well-being.

7 - Document Findings and Reporting

Finally, it’s essential to document the entire investigation process, including:

• Findings related to fatigue risks and contributing factors.
• Recommended corrective actions and timelines for implementation.
• Any follow-up measures or ongoing evaluations to ensure the effectiveness of changes.

Proper documentation helps ensure that corrective actions are tracked and followed through and provides a record of due diligence in case of future audits or legal inquiries.

Conclusion: Enhancing Safety Through Fatigue-Focused Incident Investigations

Investigating safety incidents with a focus on fatigue is crucial for reducing the risk of future accidents and enhancing the overall safety culture in your organization. By following the best practices outlined in this article, you can identify fatigue-related contributing factors, implement effective corrective actions, and create a safer, more sustainable work environment.

If you are interested in learning more about fatigue-focused incident investigations or want expert guidance in assessing your workplace, CIRCADIAN® is here to help. We offer comprehensive assessments and guidance for developing and implementing effective Fatigue Risk Management Systems (FRMS), as well as conducting scientific evaluations of safety incidents. Contact us today to learn how we can help reduce fatigue risks and improve workplace safety!