Authorities probing a fire that killed dozens at a Swiss ski-resort bar say it appears to be a textbook case of what fire experts call a flashover. Investigators in Crans-Montana believe flames at Le Constellation, where about 40 people were killed early Thursday, likely began when sparklers on champagne bottles were held too close to the ceiling, local attorney general Beatrice Pilloud said Friday. As the fire burned in the enclosed space, heat and toxic gases would have risen and spread across the ceiling, rapidly driving up the temperature. Once a room reaches roughly 1,000 degrees Fahrenheit, nearly every exposed object can ignite in quick succession, according to the National Fire Protection Association.
"All the wood, all the seats, all of the decorations, and everything else in the room would be heated to the ignition temperature," Steve Kerber, executive director of the Fire Safety Research Institute in Maryland, tells the New York Times. In such conditions, he added, especially with plastics and other synthetic materials, the transition from a localized flame to a room fully engulfed can take just a few minutes. Even firefighters in full gear are unlikely to survive inside once a flashover occurs. Fire consultant Stephen Mackenzie tells CNN that with fires producing combustible gases, in a flashover, "the smoke is actually on fire."
Kerber says flashovers were a factor in serious fires including the 2003 Station nightclub fire in Rhode Island, which killed 100 people after pyrotechnics ignited foam soundproofing. He says that while flashovers are a common feature of fires, they are not inevitable: automatic sprinklers, strict enforcement of fire codes, and avoiding highly flammable materials on ceilings and walls in crowded indoor venues can keep small blazes from turning into the kind of inferno seen in Switzerland. Dr. Robert Larribau, chief physician at the emergency department of a Geneva hospital some of the victims were sent to, tells NBC News that many victims appear to have injuries caused by both flashover and backdraft, which happens when new air reaches a fire that has used up all the oxygen in a room
Backdraft results in "immediate fatal injuries, including severe blast trauma, extensive thermal damage, and lethal inhalation of toxic gases, and is therefore more commonly observed among nonsurvivors rather than among rescued victims," Larribau says. Flashover, he says, results in "severe, often deep, burns predominantly affecting exposed body areas such as the face, neck, and upper limbs, and is frequently associated with critical inhalation injury due to intense radiant heat and superheated gases." He says survivors will need weeks or months of rehabilitation, and "many will suffer lifelong consequences."
,
uBlock 
,
and
Ghostery 
)
