The incident investigation is one of health and safety management’s most powerful tools, helping to flag systemic failings and prevent recurrences.  So, how do you conduct one effectively?

The answer begins from the moment the incident happens, because your initial response can prepare you for the investigation to follow. This will include preserving the scene, taking people’s names for witness statements and recording the environmental conditions.

You then have decisions to make on the level and timing of the investigation. Whether it is low (short time frame, carried out by relevant supervisor or line manager) or high (team-based, involving wider organisation) will be determined by the likelihood of such an incident happening again and potential worst consequences. The urgency with which you conduct it will rely on the magnitude and immediacy of the risk. In general terms, the sooner the better while the event is fresh in people’s minds.

What does an investigation involve?

You are gathering the evidence and analysing it, looking for actionable insights that can inform improvements to your risk controls. Information sources for this include physical evidence at the scene, the accounts of witnesses and the written policies and procedures in place at the time to manage the risks of such an incident happening. You are on a mission to identify both the immediate and the root causes. This is an exercise in accident prevention.

To be successful, your interviews will have that goal of prevention in mind, rather than the apportioning of blame.  A positive strategy for interviewing will give you the best results. To achieve this, the PEACE model is a tried and tested framework. In brief, PEACE stands for:

• Planning and preparation – set out a suitable location and time for each interview and make it clear from the outset the aims and objectives of the meeting
• Engage and explain – this includes assessing the needs of the interviewee, listening actively and using appropriate language
• Account, clarification and challenge – raise inconsistencies or contradictions between the interviewee’s account and other evidence
• Closure – summarise, ensure all areas have been covered and explain next steps
• Evaluation – examine whether the aims and objectives of the interview were achieved, and evaluate own performance as interviewer

Such a framework can help you remove the barriers to a good interview, such as leading questions, poor communications skills and the mindset of the interviewee. If the incident was traumatic, for example, is the interviewee in a fit state to be questioned so soon after the event? Good planning, preparation and engagement will address this.

With a robust interview process set down, you will consider the many and varied factors that can contribute to an incident. You have human factors, for example, the competence of the individuals involved, and their mental and physical state at the time. Were they tired or stressed, for example. Organisational factors are important. Here, we think about things like safety culture and work pressures. If human failings are considered a contributing factor, these do not happen in isolation, and it is important to identify the root cause, rather than just the immediate causes of an incident, to help prevent its reoccurrence

An incident investigation, at the right level, involving the relevant people and conducted with a positive interview process that avoids finger pointing, will create a clear picture of what happened, taking all the key factors into account. This clarity will help you then identify what controls need to be introduced as part of an action plan to ensure such an incident isn’t repeated. 

This article provides a brief overview of best practices for incident investigation interviews. The NEBOSH HSE Introduction to Incident Investigation qualification, developed by NEBOSH and the Health and Safety Executive, is a one-day qualification that demonstrates how to investigate non-complex incidents effectively. For more information, visit www.nebosh.org.uk/inv

Natalie Sherborne, is product development manager at NEBOSH. For more information, visit www.nebosh.org.uk/inv