hydraulic ventilation

[Jaytee]

I was woundering if anyone knows where I could get information on maximum CFM for hydraulic ventilation?

[fergus]

The February 2003 issue of Fire Enginnering has an interesting article ("Nozzle Tests Prove Firegroud Realities," pg. 71-80) that may answer some of your questions.

Hope this helps

(and webteam, I apoligize for promoting the competition)

[Jaytee]

thank you, now all i need is that issue

[WTFD10]

Mr. Paul Grimwood who posts on these forums often has a pdf of this article on his website:

http://www.firetactics.com/fe2003.pdf

[Dalmatian90]

The technical answer: A lot.

Problem with the Fire Engineering article, as they mention, is they exceded the capabilities of their test equipment.

A nozzle in a fog pattern moves a lot of air, and fog-attack tactics used "positive pressure ventilation" long before that term became popular to push heat/smoke/steam out a vented window or door. It's just the PPV fan was the nozzle and was located with the attack team.

Get the nozzle to the window, it becomes "negative pressure" ventilation.

Also, IMHO if you have more than one room of fire, I'd only use hydraulic ventilation for 10/15/20 seconds to quickly reduce the ambient temperature/smoke/steam in a room you just knocked down. If the fire isn't controlled yet, you risk drawing the fire to you. While you can be trapped by any improper ventilation, this is probably the only venting tactic that puts you in the direct path between fire and the outside! Not saying don't do it, just think about what your doing and remember most nozzle use should be a matter of seconds, not of minutes like we usually see.