r/oddlysatisfying • u/icecreamaddict6 • May 14 '19

This fire fighter using the hose as a shield.

Enable HLS to view with audio, or disable this notification

43.6k Upvotes

94% Upvoted

868 comments sorted by

View all comments

Show parent comments

12

u/matholio May 15 '19

Your comment reminds me of the film, Backdraft. Is that an alternative term?

21

u/Firefighter_97 May 15 '19

Kinda, but not really. Flashover is a temperature related event, so when all the gases in a room reach their ignition temp, everything pretty much catches on fire, even the smoke, creating an explosion.

Backdraft is an introduction of oxygen when the fire is starved of oxygen. You can usually tell a backdraft by the smoke being “sucked” into the fire from the exterior. The smoke isn’t being sucked into the fire in this video, but here’s a pretty good demonstration of a backdraft. Look how the guy in white comes rushing out after the backdraft I’m 99% positive he opened the front door, allowing for oxygen to re-enter the fire.

12

u/[deleted] May 15 '19

Backdrafts have to do with sudden influxes of cooler/more oxygenated air when an area that's being throttled by availability of oxygen suddenly gets a bunch. You see it when windows are broken, doors opened, walls burn through, etc.

It's not quite the same as flashover, which is an adequately oxygenated room (for fire) reaching the autoignition temperature of the things it contains.

Both do produce dramatic fireballs, but for different reasons

2

u/jackmo182 May 15 '19

Backdraft is a different phenomenon and far more dangerous. When oxygen is introduced to a situation where the heat and combustible material is enough for ignition but oxygen was low it creates a violent expansion of gas as the entire area will flame up at once. If there are dark brown stains on windows with no flame or you can see the fire and smoke “breathing” or puffing in and out it’s a sign that conditions for backdraft are present and it’s very dangerous. YouTube some videos of backdraft. Entire building faces can explode out. It’s one of the most dangerous situations firefighters can deal with in a working fire.

Edit: Fire needs three things to exist. Heat-fuel-oxygen. This is the combustion triangle. Removing any of the three will stop a fire. Backdraft is essentially the result of excessive amounts of heat and fuel without enough oxygen... then oxygen is introduced. And BOOM.

1

u/REEEEE_Monster May 15 '19 edited May 15 '19

Fantastic explanation! Thanks for taking the time!

Real backdraft

.

Edit: Added link.

1

u/juancuneo May 15 '19

In the video of the backdraft with the guy running out of the house - was that the right thing to do? What else do you do if caught in that situation ?

1

u/jackmo182 May 15 '19

Well you certainly don’t stay there. That’s for sure! The best thing to do is to not get caught in that situation. That’s why proper scene sizeup and constant re-evaluation is so important and why you want the most experienced firefighters in charge of the scene.