28 avril 2022

Mettre l’accent sur ce qui marche a parfois plus de sens que comprendre pourquoi ça ne marche pas

A fundamental safety management assumption is the need to learn from accidents, to identify their causes, and to take steps to prevent their recurrence. Safety by prevention is, however, not the only solution. Since something cannot go well and fail at the same time, another approach is to learn from situations where things go well and where « nothing » seems to happen. In the present case a computer breakdown led to the loss of most of the information in an air traffic control system. The operators managed to compensate for the missing information and keep traffic flowing, although with reduced capacity, while the technical staff managed to restart the system. The same breakdown occurred two more times during the day but in both cases the operators were able to compensate. In the evening the computer system was restored and no further breakdowns happened. The organisation investigated the event but since it focused on the technical issues the lessons learned were in terms of new checklists, improved procedures, and stricter precautions. The paper presents an analysis from a different perspective that looks at what went well. This identifies a number of things that may contribute to make performance in the future even safer

  • Une remarquable et très didactique illustration du fait qu’il y a plus à gagner à tirer des enseignements de ce qui a bien marché après un incident sévère (une panne informatique dans un centre de régulation du trafic aérien) plutôt que s’acharner à débusquer des causes racines pour éviter que cela se reproduise. Non que prévenir une récurrence soit vide de sens, mais la recherche des causes n’est pas une garantie de succès, tandis que les solutions mises en place pour pallier l’événement sont riches d’enseignements pour mieux faire fonctionner le système à l’avenir.

Hollnagel E, Laursen T, Sørensen R. A day when (almost) nothing happened. Saf Sci 2022. Doi : 10.1016/j.ssci.2021.105631147.