Ventilating very large structures

[myersdl]

I am interested in hearing from anyone who has had success in ventilating very large structures (warehouses, malls, etc) using PPV. Our truck companies and heavy rescues have the largest gas and 220vt electric fans on the market but are still unable to generate enough CFM's to efficiently clear the larger open structures in our fire district. We have considered truck or trailer mounted "monster fans" as a regional resource and are wondering if anyone else has gone this route with success.

[PaulGRIMWOOD]

Largest?

The Groupe Leader PPV units (MT296) the push in excess of 57,000 cu.ft per min are the market leader in terms of portable PPV air movers! These have successfully vented several large structures in the UK. I am told the fans are available in the USA.
www.groupe-leader.com

[Looper]

We use a trailer mounted fan (48" prop) powered by a 40hp two cylinder engine (originally from an ultra-light plane). We have sucessfully ventilated strucures up to 500,000 sq ft. It automatically responds to all of our commercial and church fires, and frequently makes long distance mutual aid runs. The Houston FD also has one that is powered by a car engine.

I think Supervac makes a trailer mounted PPV fan that has a 8' prop and is powered by a Chevy 454 V8.

[FFMcDonald]

Well --

I was originally going to respond- and tell you about the Ponderosa VFD outside of Houston, TX -- I know that they have a fairly large fan...

I know of it because one of the guysI go to college with dragged me down to Texas to run a few calls with them.... anyway -- I was beaten to the punch by Looper.......

they may have a picture of it on their website... I belive it isPonderosa FD

Hope that helps.....

[BillyMott]

I just recently read that a Dept. used a trailer mounted Air Boat to vent a large area. I don't know the size of the motor or prop tho. Depending on your area some might not have one of these available to them.

[res7cue]

Billy Mott, That was Cabin John VFD in Montgomery County MD.

[engine1321]

Around in my area, we have several buildings that have automatic ventilation shafts in the roof, kind of like a fire sprinkler. When the frangible bulb breaks, the truck crews better watch out because those doors will spring up rather quickly, so normally we don't have to worry about PPV's.

[Rescue101]

The air boat is the balls!A double duty rescue boat/vent fan.One of the Fla. guys should be able to give you a CFM on these but it's right up there.T.C.

[Inferno]

I am wondering if this is really necessary? There was a small fire in a local mall a short time back and my department used 2 fans placed properly at 2 doors at one side of the mall. All other doors were kept closed except the door in which we wanted the smoke to exit. In about five minutes, the entire mall went from light smoke conditions to crystal clear. We don't have that large of a mall. It's a strait building about 600 yards in length (including the two stores on each opposing end.) I was in complete awe when I saw how well a 220 volt and a same-sized gas powered fan moved such a large volume of air. I think that the keys to moving large volumes are:
a) a good seal around the doorway with the fan (six to eight feet away.)
b) one egress, one entrance for the air.