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Sparklers near ceiling suspected in Crans-Montana blaze
Swiss investigators believe sparklers attached to champagne bottles held too close to the ceiling ignited the catastrophic New Year's Eve fire at Le Constellation bar in Crans-Montana, killing at least 40 people and injuring 119.
How the fire started
At a Friday press conference, Valais regional attorney-general Béatrice Pilloud stated that evidence points to sparklers on champagne bottles being raised too near the ceiling as the likely ignition source. BBC Verify analyzed survivor and bystander footage, including two widely shared images showing patrons holding lit sparklers above their heads just before flames appeared on the ceiling.
One image captures five bottles with sparklers, while another shows a person in a crash helmet perched on someone's shoulders, holding a bottle with a lit sparkler closer to the ceiling. BBC Verify confirmed the images were taken after midnight on January 1 using bar design details and pipework for verification, ruling out AI manipulation.
Flammable ceiling material under scrutiny
Fire safety experts told BBC Verify that the ceiling padding visible in photos resembles untreated polyurethane (PU) foam, commonly used for soundproofing but highly flammable if not treated with fire retardants. Dr. Peter Wilkinson of Loughborough University noted that once ignited, PU foam can spread flames rapidly and emit dense, toxic smoke, drastically reducing escape time.
Professor Edwin Galea of the University of Greenwich added that fire-retardant treatments on PU foam can degrade over time. Swiss authorities have not confirmed the type of foam used in Le Constellation or whether it met safety standards.
Flashover and escape routes
Officials described a "flashover" event, where superheated gases accumulate at the ceiling and ignite the entire room almost instantly. Michael Klippel, a fire safety expert at ETH Zurich, stated that survival after flashover is rare.
The bar spans two levels-a ground floor and basement-with the fire believed to have started in the basement. Videos show patrons attempting to extinguish flames before fleeing up a narrow staircase, a potential bottleneck during evacuations. Professor Galea noted that panicked individuals in unfamiliar spaces often exit through the route they entered, even if other exits exist.
While officials confirmed multiple exits, they could not verify if the emergency exit was open during the fire. Valais state councillor Stéphane Ganzer stated the building was equipped with an emergency exit, though most survivors exited through the main entrance.
Safety inspections and prior incidents
The Office Cantonal du Feu (OCF) of Valais oversees annual fire safety inspections for venues like Le Constellation. BBC Verify has requested access to past inspection records but has not yet received them.
One of the bar's owners told local media the establishment had been inspected three times in the past decade, with all checks complying with regulations. However, investigators are reviewing additional footage, including a 2024 video showing sparklers attached to bottles being used inside the bar, uploaded by the bar's official YouTube account.
Next steps in the investigation
Investigators continue to analyze survivor testimonies, including interviews with the bar's two French managers and escapees. Authorities are also examining the bar's exit routes, ceiling materials, and adherence to safety protocols to determine the full sequence of events that led to the tragedy.
