Time for another episode of “My Search History is Scary.” As a person with a deeply rooted fear of fire (a fear I passed along to my detective DI Nigella Parker . . . yes, I am that kind of person), I found much of what I had to research while writing And by Fire to be frightening.
As part of my how-do-things-burn, fire science research I had the opportunity to attend a seminar given by a regional assistant Fire Marshal and arson investigator. One of the events he discussed was called a flashover. If you aren’t terrified of flashovers then you don’t have any idea what one is.
A “flashover is a thermally-driven event during which every combustible surface exposed to thermal radiation in a compartment or enclosed space rapidly and simultaneously ignites,” [U.S. Fire Administration]. According to the seminar-giving arson investigator, it is nearly impossible to survive a flashover—even in personal protective gear that is rated to 1200 degrees. And it’s not like the average person is in possession of that gear anyway—that’s for the professional firefighters and they don’t often walk out of flashovers alive even so.
A little background. Starting with the definition of a “flash point.” A flash point is the lowest temperature at which a particular vapor will ignite if given an ignition source (e.g. that pot on your stove that caught fire). The flash points for different materials occur at different temperatures. An item is considered “flammable” if it has a flash point of less than 100 degrees. It is considered “combustible” if its flash point is over 100 degrees.
A flashover is when all flash points are exceeded and EVERYTHING in a room that can ignite does ignite in a single, horrifying and dramatic moment.
Why should you care as a civilian? Because if the house you live in catches fire you have a lot LESS time than you think to get the hell out before you are caught up in a life-ending flashover. According to the arson inspector your great grandma had a lot more time. Back in the days before petro-chemical related products in homes—when couches had a wool or cotton fabric covers instead of a synthetic ones and were stuffed with horsehair and springs, and when construction materials were old-style—great grandma and her kids had, on average, about thirty minutes before that Ohio farmhouse flashed over leaving whoever was left inside dead (and crispy).
How long do you have today? Sorry but on average the occupant of a modern home with modern furniture products has LESS THAN 5 MINUTES to get out before a flashover occurs.
So, forget saving any material objects!!! Grab the kids and the dog and get out as fast as your legs will carry you!
For a video of a flashover check out this demonstration provided by the Oak Ridge Fire Department.
You’re welcome, and check those smoke detectors (you need that early warning).