AcciMap graphically maps the multiple contributing factors to an accident and their inter-relationships onto the following six levels:

  1. Government policy and budgeting
  2. Regulatory bodies and associations
  3. Local health economy planning and budgeting (including hospital management)
  4. Technical and operational management
  5. Events, processes and conditions
  6. Outcomes

Figure 1 represents AcciMap analysis of the insulin over-prescription incident.

Figure 1 AcciMap Analysis of the Insulin Over-prescription Incident

The AcciMap approach was developed by Rasmussen (1997) as a means of modelling the socio-technical context to identify the combination of events and decisions that produce an accident. Each level is involved in safety management through laws, rules, and instructions. For systems to function safely, decisions made at high levels should trickle down and be reflected in the decisions and actions occurring at lower levels of the system. Conversely, information at the lower levels (e.g. staff, work, equipment) regarding the system’s status has to travel up the hierarchy to inform the decisions and actions occurring at the higher levels. Without this so called ‘vertical integration’, systems can lose control of the processes and fail.

Notably, Accimap is a generic flexible approach since it does not use pre-defined taxonomies of failures across the different levels. It is relatively simple to learn and use, but the analysis could be time-consuming and the output could become large and unwieldy.

AcciMap approach has been used to analyse accidents in various domains, e.g. aviation  (Branford, 2011), patient safety (Waterson, 2009), outdoor activities (Salmon et al., 2012) and marine transportation (Kee et al., 2016).


sewol paper

  • Branford, K., 2011 Seeing the big picture of mishaps: applying the Accimap approach to analyse system accidents. Aviation Psychology and Applied Human Factors, 1, 1, 31-37.
  • Rasmussen, J., 1997. Risk management in a dynamic society: a modeling problem. Safety Science, 27, 2, 183-213.

Practical resources

Beginners guide to MS Visio for AcciMap (PDF)

If you want to have a Microsoft Visio Template for AcciMap, please contact Thomas Jun (