During a press conference following the deadly fire at a Swiss resort, Béatrice Pilloud, attorney general for the Valais region, said she believes a “flashover” impacted the fire.
The technical term indicates that everything in the room caught fire almost simultaneously, which resulted in an explosion in the Le Constellation bar.
“There are many circumstances to be clarified. The main theory we are prioritizing is a flashover that caused a quick explosion. Several statements were heard and there are phones recovered to be analyzed,” said Pilloud.
A flashover occurs when hot gases rise to the ceiling and spread through walls, according to the National Fire Protection Association (NFPA).
The heat intensifies until .
“Flashover is when you no longer have objects in the room on fire. The entire room is on fire,” Steve Kerber, vice president and executive director of the Fire Safety Research Institute, told CNN.
As temperatures rise to as high as 538°C, even firefighters in full protective gear have little chance of survival, according to the NFPA.
“Imagine you have an entire ceiling spreading fire very quickly, the amount of energy coming from that ceiling falls onto every other combustible object in the entire facility,” Kerber explained.
“All the objects basically catch fire in very quick succession, and then the entire room is engulfed in flames, which is fatal.”
