Two days after the explosion of an apartment building on rue de Tivoli, in Marseille, the marine firefighters are still looking for four missing people. Four bodies have been pulled from the rubble since the building collapsed on the night of April 8-9. Co-founder of the Emergency Architects foundation, Patrick Coulombel analyzes for Le Monde the "difficulty factors" for the emergency services.
Buried victims, fire, fragility of neighboring buildings: the situation combines the difficulties of intervention. The presence of missing people under the rubble, potentially still alive, complicates every movement. The responders must be infinitely cautious, when the stake – the hope of survival – nevertheless requires wasting as little time as possible and clearing away what can be cleared as quickly as possible. The site [rue de Tivoli] sets two limits to rescue operations. The fragility of the outlying buildings first requires extreme vigilance to protect responders and buried persons. The geography of the places, small dense streets, can then prevent the use of certain more massive and efficient machines.
A fire starting after a collapse is not uncommon, and the causes can be multiple: gas leak, materials used in the affected buildings, faults in an electrical installation, oil heating... Fires resulting from earthquakes are also very common. They are sometimes even more devastating and deadly than the initial collapse of the dwellings, as in Japan in the 1920s [in 1923 in the Kanto plain].
In Marseille, this fire in the lower area of the rubble further complicates the rescue of possible survivors. Moving or handling any part on the surface can create drafts and fuel combustion. Extinguishing the fire from a distance is not easier. Overwatering the crumbling area runs a double risk: weighing down the entire structure and causing settlement; drown the victims trapped under the rubble.
Each French rescue service has trained specialists in rescue and clearance. In Marseille, the body of marine firefighters is mobilized for this type of operation. It is the cream of the crop, among the most competent teams in the world. Both emergency and military professionals, they are recognized everywhere for their responsiveness. Clearly, no one, and not only in France, could really do better than them in these conditions.
Explosions and then collapses of buildings in France caused by a gas leak are a known phenomenon, not totally rare, even if it is difficult to quantify it or to identify the share of falling buildings linked to this risk. In the present case, in the absence of more precise elements from the authorities, we cannot today draw any conclusion on the origin and the mechanism leading to the collapse.
But the prosecutor's office itself reported an "explosion." Such a phenomenon, caused or not by the gas, affecting the ground floor of a building or a load-bearing wall, can logically lead to the fall of the whole. Even that of nearby buildings, affected by the blast of the initial explosion or collapsing like a house of cards following the disappearance of the neighboring construction. The last two days have shown the need for the clearest and fastest possible communication from the authorities on this subject. To prevent and inform the inhabitants and residents concerned, first. But also to avoid the propagation of hypotheses by those who know nothing. More than thirty-six hours after the explosion, we still know very little...
