Everybody who witnessed the accident is rattled by it. A dramatic event. How is such a thing possible?
What is seen in the video is three pontoons on two of those a mobile crane is positioned. On the third the bridge part that needs to be inserted in the Juliana bridge a bit further down the stream. It all looks technically well prepared for the many spectators present. What can go wrong?
A chain reaction is started of no known origin as yet and no human interference can change the course of events. Buildings in close proximity of the cranes are crushed by the bridge part and both cranes. In just a few seconds what looked like a professional arrangement falls to pieces.
Are all necessary precaution taken? If so, probably not sufficiently. Often the causes of these complicated accidents are a mix of coincidences, which were not thought of. Therefore high risk companies, for instance the ones which handle dangerous substances, pay a lot of attention to risk assessment. Reviewing all kinds of scenarios, that can lead to accidents with damage to health, environment or otherwise. For each identified risk precautionary measures are defined and constantly tested for their adequacy. To which extent the companies involved in the accident at Alphen aan den Rijn should comply with equal measures and legislation, is to be determined by others. When all imposed precautionary measures were taken, this accident is a disaster of unknown origin. The security council will probably not accept such an outcome.