ABSTRACT
Key Points .............................................................................................................. 151 Disappearance of the Accidental ............................................................................ 152 Drifting into Failure ............................................................................................... 153 Banality, Conflict, and Incrementalism .................................................................. 156
Drift into Failure and Incident Reporting .......................................................... 159 Systems Thinking ................................................................................................... 162
Systems as Dynamic Relationships ................................................................... 162 Modeling Live Sociotechnical Systems ................................................................. 164
Drift into Failure as Erosion of Constraints and Eventual Loss of Control ...... 165 Creation of Local Rationality ............................................................................ 167
Accidents actually do not happen very often. Many industries have reported a drop in their injury and fatality rates over the past decades. There are even systems in the developed world that are, as measured by fatality risk, even ultra-safe. Their likelihood of a fatal accident is less than 10−7, which means a 1-out-of-10,000,000 chance of death, serious loss of property, or environmental or economic devastation per activity or operation (Amalberti 2001). At the same time, this appears to be a magical frontier. All systems that get there go asymptotic after this. No system has figured out a way of becoming even safer. Progress on safety beyond 10−7 is elusive. As René Amalberti has pointed out, linear extensions of current safety efforts (incident reporting, safety and quality management, proficiency checking, standardization and proceduralization, more rules and regulations) seem of little use in breaking the asymptote, even if they are necessary to sustain the 10−7 safety level.
