How was it that fire ravaged Notre-Dame? And how was it saved?
A New York Times investigation found that a miscommunication among security employees and flawed planning let the fire spin out of control in one of France’s most revered monuments on April 15. When the firefighters were called, it was already too late to stop it from spreading.
Some 500 firefighters battled the blaze into the night. Some, at the peril of their own lives, went inside the northern tower to protect it from flames at a moment when it could have collapsed at any time. This decisive moment saved the structure.
Here is what the investigation revealed about a foretold tragedy, and how the worst was averted.
Security employees couldn’t locate the fire and waited 30 minutes before calling the firefighters.
After the first warning light flashed with the word ‘Feu,’ or fire, at 6:18 p.m. on April 15, a fire security employee monitoring a control panel at the cathedral radioed a church guard by walkie-talkie, so he could go to check if there was actually a fire. This is a general French practice.
But the church guard went to the wrong place: instead of walking up to the cathedral’s attic, he went to check the attic of an adjacent building, the sacristy. It is unclear whether the security employee misread the message, or if the church guard misunderstood it, but neither could locate the fire.
The security employee assumed it was a false alarm and tried to deactivate the system. He didn’t call the firefighters. In the meantime, the church guard stayed in the sacristy.
After several phone calls among employees and 25 precious minutes wasted, a manager finally gave the right order to the church guard: go to the cathedral attic. Only when the church guard located the fire there, at 6:48 p.m., did the security employee finally call the firefighters.
The design of the fire alarm system was riddled with faulty assumptions.
Archival documents found in a suburban Paris library show that it took six years, dozens of experts and thousands of pages of documents to set up the fire warning system at Notre-Dame.
With more than 160 detectors and manual alarms, it seemed elaborate enough to detect any smoke and send an alert. Yet little was done to prevent a fire from spreading: There were no sprinklers or firewalls in the attic. The alarm message was hardly understandable.
What was designed to generate a quick response led to a critical loss of time.
“The whole outcome of it is this clumsy human response,” said Glenn Corbett, an associate professor of fire science at John Jay College of Criminal Justice in New York. “You can spend a lot to detect a fire, but it all goes down the drain when you don’t move on it.”
On top of those flaws came the inexperience of the security employee monitoring the control panel, who had been working at Notre-Dame for just three days. He had never been to the attic.
“The only thing that surprised me is that this disaster didn’t happen sooner,” said Albert Simeoni, the head of fire protection engineering at Worcester Polytechnic Institute in Massachusetts.
The delay in calling the firefighters left them in a nearly impossible position.
The first firefighters reached Notre-Dame shortly before 7 p.m., when the cathedral was already engulfed with flames. They couldn’t contain the flames on the roof, which were whipped up by winds that pushed the fire toward the towers.
When the spire collapsed, it sent a fireball through the attic. Some firefighters were just a few feet away. Yet none were killed.
The collapse set the firefighters back further after a critically late start.
“It’s like starting a 400 meters several dozen meters behind,” said Gen. Jean-Marie Gontier, the Paris brigade deputy fire chief, comparing the fight to a foot race.
The cathedral was dangerously close to collapsing.
After the spire collapsed, the fire brigade general overseeing the operations convened a critical meeting and decided to throw everything into saving the towers, focusing on the northern one, already on fire.
That probably saved the cathedral.
Inside the northern tower, eight giant bells hung precariously on wooden beams. The firefighters feared that if the beams collapsed, the falling bells would act like wrecking balls and destroy the tower.
“At that point, it was clear that some firefighters were going to go into the cathedral without knowing if they would come back out,” said Ariel Weil, the Paris mayor of the 4th Arrondissement, where Notre-Dame is.
Inside the northern tower, a group of firefighters reached a floor at the height of the bells, where they were able to battle the flames back. One firefighter almost fell through the wooden, cracking steps.
By 9:45 p.m., they had tamed most of the flames.
What caused the fire? We still don’t know.
Investigators have said that the fire may have been caused by a short-circuit in the electrified bells of the spire, or in the elevators that had been set up on the scaffolding. Cigarette butts, left by workers and found on the scaffolding, are another possibility.
Church and fire security employees have been blaming each other for the miscommunication and delay in calling the firefighters. Investigators have yet to say who was responsible.