Backdraft Video

[Captainron19]

No sound but a good training video to show the signs of a backdraft about to happen

View the video at this link:

http://fire-forums.com/forums/showthread.php?t=453

[NWOhio157]

This is a good video... but it's a repost.

I'm not holding anything against you. I understand the search feature is ineffective these days.

http://forums.firehouse.com/showthread.php?t=85692&highlight=backdraft+video

[Captainron19]

This is a good video... but it's a repost.

I'm not holding anything against you. I understand the search feature is ineffective these days.

http://forums.firehouse.com/showthre...ackdraft+video

No problem - and to make things worse - I posted it twice - having trouble with using the forum - I think it has something to do with my new PC using Internet Explorer 7 - I am having trouble with using any forums.

[jccrabby3084]

Hey I like re-posts...I might have missed it the first time.

[Captainron19]

Hey I like re-posts...I might have missed it the first time.

LOL Then I am the man for the job! I swear sometimes I am afraid I may leave for work and forget to put my pants on ( ) cuz I got so much going through my mind sometimes !

That's pretty wild. It's pretty impressive that a fire that was already venting that well could explode as powerfully as it did. Anyone know what triggered this? An open door or a broken window?

Btw Capt. Ron, do you recognize my name?

[Dalmatian190]

Below is the background I've since found on another YouTube posting.

First...just a comment, and it's something I'm still researching in a number of fire service books. I believe there's a difference between a "Smoke Explosion" and "Backdraft" despite many magazine articles, some books, and a lot of training that confuses the terms.

While I haven't settled on a final "definition" the characteristics for the proper definition of each seem to be:

A Backdraft is a vent-driven event of a "stale" fire (decay stage) when fresh air is introduced to a space that is filled with a hot, fuel rich atmosphere. It begins at the vent point and works "backwards."

A Smoke Explosion occurs during an active, well vented fire. The turbulent "boiling" smoke is a key condition for it to occur -- according to the research, the turbulence allows a flame front to propogate faster. When conditions are right, the fuel mixture "explodes" deep in the fire -- which is why you see the substantial column of smoke being pushed out ahead of any actual flames in these events. It's an explosive fire development during a fire still in a growth (not decay) phase.

This incident I would consider a "smoke explosion" from what I've seen / read on it.

Daniel's Block Fire:

Shortly after companies were in the building removing occupants. The plate glass storefront on the mercantile space dropped out lazily and smoke began to poor out of the store. Command reported the conditions to the companies operating on the upper floors, 2, 3 & 4 that a fire condition was present on floor 1. Eng-3 officer replied that the smoke and heat condition on the upper floors had deteriorated significantly and that the smoke was "Boiling" out of the floors and walls. Eng-3 officer gained accountability of the 7 members on the upper floors and began exiting the building. At the same time fire began blowing out the front of the store. Members using hooks removed all of the plate glass from the storefront. Within seconds heavy fire was blowing out of the front of the store on #1 floor and extending up the front of the building over the roofline. All firefighters were ordered out of the building. Within 5 minutes of the firefighters exiting the upper floors the second floor collapsed.

A defensive operation was ordered and 2nd-3rd-& 4th alarms were transmitted. Free burning fire continued as heavy master streams and big lines were put in to operation.

At approximately 01:33 20 minutes after the fire broke out and free burning fire was involving the structure on floor #1 & 2 the Backdraft occurred.

The backdraft was intense and forceful. It is believed that accumulation of gases in the basement of the building were building up and eventually let go. Precautionary measures of taking out the plate glass storefront were beneficial in reducing personal injury.

When viewing the footage it appears that memebers were directly in front of the building, however members were at 45-degree angles to the front. Operating lines. All members operating were in full protective clothing and SCBA. This helped reduce injuries as well. Engine 1 personnel operating in the rear of the building trying to force a door were blown back across a parking lot when the backdraft occurred. The top portion of the steel door folded from the force.

This video was taken from a police cruiser parked approximately one block away. You see signs of smoke churning at this angle. From the front of the building the smoke did not appear that way.

This backdraft occurred after ventilation had been completed and heavy fire burned for over 20 minutes involving the structure as well as contents. In addition, heavy streams operated on the fire well before the backdraft occurred.

We have experienced these types of building fires before. The large open spaces and concealed spaces allowed these gases to build up to explosive concentrations. Proper PPE certainly helped prevent injuries to our members. It was clear to us that this fire had been concealed within the walls and floor of this building and burning for a period of time before it was reported. The balloon frame constructions allowed for this fire to go unnoticed and gain headway

[Edward Hartin]

Backdraft or Smoke Explosion

Dalmatian is correct that a backdraft is a vent initiated event. This type of extreme fire behavior results when air is introduced into an hot, ventilation controlled fire (high concentration of CO and excess pyrolizate).

However, A smoke explosion is considerably different in that it involves ignition of a mixture of products of combustion or pyrolizate that is within its flammable range (such as might accumulate in a void space or attached exposure).

For a good explanation, see page 17 in Enclosure Fire Dynamics by Karlsson and Quintiere. Also see Extreme Fire Behavior - Backdraft and Extreme Fire Behavior - Smoke Explosion in the members section of firehouse.com.

Cheers,