Since We're Talking Ventilation....

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Permalink Reply by Jeff Schwering on May 28, 2010 at 3:37pm

Amazing, just freakin Amazing, and we wonder why we kill firemen in training! Thanks for posting this Brother, I believe years ago I saw something similar, but not quite as dramatic, when I worked at another county dept.

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Permalink Reply by Dan Rice on May 30, 2010 at 1:02pm

This is a great video of improper PPV and the detrimental effects it can have to the firefighters that enter, and also the rapid destruction it can cause to the property we are supposed to protect is amazing. Issues like this are large contributing factors to why our safety standards continue to be more strict but our LODD are holding strong. Train train train, thats all we can do

Be safe, train hard
D.Rice

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Permalink Reply by Brian Arnold on May 30, 2010 at 5:19pm

Dave and Dan,
Perhaps you could give us an idea why it's a classic example of improper PPV? I didn't ever get to see the exterior opening on the charlie side of this structure. Do either one of you have more insight into this video?

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Permalink Reply by Larry Lasich on May 30, 2010 at 6:43pm

Brian Arnold said:

Dave and Dan,
Perhaps you could give us an idea why it's a classic example of improper PPV? I didn't ever get to see the exterior opening on the charlie side of this structure. Do either one of you have more insight into this video?

Brian; First of all, it's a Golden Rule that you never (ever) start PPV (in this case, it's called PP Attack) with crews inside. You are about to change in a big way how the fire is developing. Best to do that from a safe position. Second; you set the Fan up in the door so that the top of the door is outside of the cone and you watch for smoke and flame coming out from the top of the door. This will tell you that there is too small of a vent opening. Call the outside vent crew and ask for more (in the fire area, of course). If the vent opening is large enough, you will see light smoke from the top of the door frame. This will indicate that conditions inside the door are improved for your attack. Third; the Officer (either Company or Safety) should have caught the smoke conditions (pushing hard, dark, thick, coming out the doorway close to the floor and rolling out of the eaves) and evacuated everyone until the event was over.

Positive Pressure Attack has to be followed quickly with hose lines, remember; all venting helps the fire to grow.

Larry

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Permalink Reply by Dan Rice on May 30, 2010 at 7:22pm

Brian,
I will have to look and see if I can find the video on this I have seen before. It shows about three or four different angles of this structure through the duration of the incident. The way this was set up as training was arriving on the scene with a working fire if I remember correctly. Keep in mind that my opinion is one of someone that does not approve of a PP attack in the first place so i'm a little one sided. If I can find that video I'll shoot ya the link. Thanks

Be safe,
D.Rice

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Permalink Reply by Brian Arnold on May 31, 2010 at 4:10pm

Gentlemen,
My point exactly! It's not PPV, but rather a poor example of of PPA. PPV is a tactic that should be utilized after knockdown of the fire. The proponents of PPA state, as Larry identified, that the fan should be started prior entry and conditions observed for 60-90 seconds prior to entry. Crews in this video were working inside for much longer than this prior to the fan being fired up. But what we cannot see from this video is the size of the exhaust opening. PPA proponents also state that if the exhaust opening is not large enough to facilitate a positive flow of products of combustion you should open additional windows and exhaust openings or open the adjoining windows. I have many issues with the unknowns of PPA and would challenge; as I have before, how do you enlarge a window opening that is being increased in BTU production by as much as 60%. The fire and heat blowing out of the window; if the room door is open, is too great and generally cannot be enlarged. Secondly, if you start taking windows in adjoining rooms you will draw the heat and smoke into these rooms and decrease the probability of survivability for victims in those rooms. Again, only if those doors are open to begin with.
I haven't seen the Charlie side of the structure in this video so I cannot comment on opening size. But I have been around enough structure fires and acquired structure training burns to tell you that employing the fan in the front door anytime during the fire attack is a crap shoot and can get you or the civilians you are trying to save in a world of trouble.
Unfortunately many firefighters do not spend the time to educate themselves in the differences between PPV and PPA and employ the fan incorrectly many times.

Leave the fan on the truck until after knockdown. PPA has limited applications and should only be used when specific conditions are known.

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Permalink Reply by Dan Rice on May 31, 2010 at 8:10pm

Great point Brian, I am one that has not takin the time to further my education on PPA (and yes I used the wrong terminology). It is something I know enough about to not appreciate the potential outcome if one very small variable goes wrong. Thank you for the info!

D.Rice

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Permalink Reply by Jeff Schwering on May 31, 2010 at 8:38pm

Brian, folks use the wrong terminology regularly, unfortunately. We pull our fan off on a working fire, but it is not used until the interior officer has a knock on the job. I've seen ppv cause a issue where I used to work back in the 80's. It was new, training burn in a old motel. They took out 1 little block of a widow, started the fire, sent the crew in and turned on the fan, similar to the clip, I was on the safety line, that went in and covered the initial crew as they were bailing out, minor burns, but could have been much worse. A tool in the wrong hands in our business is a major hazard, sorta like askin me to change spark plug!

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Permalink Reply by Brian Arnold on May 31, 2010 at 10:14pm

I too have used the wrong terminology before and am sure will use the wrong terms again. I have seen this video before several years ago and would truly like to see the exhaust opening. PPA and PPV can be useful tools when used properly. Fog nozzles have their place along with smooth bores. Direct attack, indirect and combination all have their place as well in the proper setting. My point being was that there are no absolutes in the fire service. I've been on attacks where the fan was called for as the seat was being hit with the initial hoseline but after horizontal or vertical ventilation had taken place. While this wasn't a true PPA or PPV it worked well as long the communication between the attack and vent crews was maintained. I am the first to tell everyone I'm not a fan of the FAN, but it does have its place. Dave's point is another reason for late placement of the fan, it blocks egress and hose line advancement. Good discussion about this topic!

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