As most of you know, I'm a float officer. I get to see a lot of apparatus set ups. Each morning when I report to my daily assignment, I check to see what nozzles each preconnected handline has on it. Usually, I find the 2.5" attack line with the traditional stacked tip smooth-bore nozzle. Given the choice, I think we can do better.
As an officer that has been on a few BIG residential fires (Type V lightweight wood) where the attic is heavily involved prior to our arrival, we need to quickly get upstairs with a RhinoChaser (BigGun), a bunch of brutes with hooks, and singular mission: pull the ceilings and put lots of water on the fire. This is our only hope for success (absent CAFS, but that's a future posting).
With significant attic involvement and a quickly progressing fire, I've found that both the roof sheathing, and some truss chords, fail pretty quickly. What is important about those two facts is that the fire and water stream are no longer contained to a structural compartment.
When aiming the stream of a smooth-bore nozzle into the fire with no structural compartment to deflect off, most of the water shoots straight through the fire, usually landing on the adjacent garage roof, in the back yard, or if you're lucky the firefighters breathing air in the front yard.
It is my opinion that the best nozzle for a preconnected 2.5" attack line is a fog nozzle. When fighting the same conditions as mentioned above you have the option to open the nozzle to a medium to wide pattern and absorb more BTUs, cool (thereby extinguishing) more structural components, and better protect the firefighters working just below the fire from radiant heat.
Some would make the argument that smooth-bore nozzles give a less-broken pattern at further distances. In my completely unscientific testing, I find that the difference at very long distances is negligible. If the decision is made to go to a defensive attack, we can always change to a smooth-bore nozzle on the exterior when the pressure of the firefight is not quite as critical. In my experience, interior structural firefighting is an up-close-and-personal event. Meaning we usually cover distance through hoseline advancement not lobbing a rainbow of water toward the glow.
*Just as a note the majority of fires in Howard County are fought by use of preconnected handlines we very rarely extend or build attack lines.
I would like to see the 2.5" fog nozzles be placed with a breakaway option. This would allow the big line inside a wood frame house with the fog and the breakaway option to either extend a line or to use as a smooth bore for industrial/commercial fires where reach and penetration could prevail.
ReplyDeleteBe safe,
Tim A
That's not a bad idea as long as the default is with the fog nozzle on. Thanks for you comments Tim.
ReplyDeleteJohn, you and I have talked about this subject before and I still cringe every time I see a video with an attic fire and straight streams of water flying out of a hole where the roof used to be.
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