It was brought up at a discussion at training about a quick window fog stream attack prior to interior attack on a confirmed room and content fire, what is everyones thoughts on this?

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What are you talking about?  Once again you're putting words in my mouth.  Where did I say that there's only two extremes to determine on whether or not to make an aggressive attack?  I really don't understand one point of your post.

Jason,

Which steam theory was thrown out the window? The one where water expands by volume 1700 times?  Or the one that says if takes large amounts of heat to produce steam and thus cooling the surrounding area?

Water converted to steam expands at ~1700 times the original volume of the water, or 1 gallon of water = 1700 gallons of steam (or ~227 cubic ft. of steam). In an enclosed space, say a bedroom that is 15ft x 10ft x 8ft high = 1200 cubic ft., so 5 gallons of water would instantly expand to fill the entire room with steam, thereby displacing the previous atmosphere.  Nothing but steam means no oxygen, no oxygen means no fire.

To accomplish the phase change requires extreme amounts of heat.  When water is converted to steam, it removes heat from combustion, removing heat from the fire and cooling surfaces and reducing radiant heat.

So steam 'smothers' the fire initially, and then cools the surroundings preventing re-ignition.

Again, which part of steam theory has been discarded?  Bear in mind, this discussion is about a R&C fire.

Oh yeah, and what's the problem with fog nozzles?

Oh yeah, and what's the problem with fog nozzles?

 

ROTFLMAO

 

I know you did not just go there, did you Jack?

*tweak*

 

Gonna get some popcorn.

Jason,

 

I was talking about 10 gallons of FLOW, not how much it takes to fill the line.  Because for damn sure it doesn't take 750 gallons to fill 250 feet of 1 3/4 inch line.  If you are using 750 gallons in a room and contents fire you are floating the fire right out of the room.

 

Really?  Using an indirect attack, in a closed compartment, with no victims in the compartment, and combination nozzles, went out the window in the 1980's?  I am going to try and not be harsh here in my response, but seriously, this is so stupid as to be laughable.

 

I am a fan of smoothbore nozzles myself, but I would bet that the majority of FDs across the nation use combination nozzles.  The nozzle itself does nothing without human intervnetion, including selecting the pattern.  We train our guys to use a straight stream for fire attack, and the fog for ventilation or overhaul.  But whether you like it or not the indirect attack is still a viable technique for fire attack.  It is nothing more than another tool in the tool box.

 

 

 

 

What words did I put in your mouth?

 

You did cite two extremes with your "safety sallies" cpmment and "get inside and put the fire out" comment.  Those were your words, and I didn't put them in your mouth.

 

One other thing - when you swore to protect life and property, did you ever consider that the lives we're supposed to protect include firefighters' lives?  

 

You also made a false assumption - that property cannot be protected except from the interior.   We protect property every time we protect an exposure, we protect property every time we give a flashover a shot from the exterior to stop the combustion quickly, and we protect property every time we extinguish the fire by whatever method is chosen.

 

The questions we should be asking include a lot more variables than just "go inside and put it out".  In lighweight, non-dimensional construction with the kind of fire shown, all too often that results in well-intentioned firefighter suicide missions.

 

 

Fire attack, the tactics that are initiated based on the strategic goals are dependant upon certain variables. You can use all the acronyms, follow the advice of the never-ending writings of text book authors, bloggers, and forum phantoms (such as myself) but basically it's a process that is fairly simple when you consider the most important factors. It is these factors that comprise the variations in approack from community to community. Staffing. Response time. Construction is right in there as well.

I beleive what is truely lost in the the tought process by many is that you have to have the mental forsight to remove yourself from YOUR world, and all that relates to what, and how you do things. Becouse it just isn't equal for all of us.

 

The vast majority of younger firefighters, and many of the vets as well cannot grasp the realities of what is accepted as, or considered to be firefighting, or fire protection outside of their world. That domain may consist of their exposure to their local level, or county. But things actually may be different in concept and practice 50 or 100 miles away from your station. And it's either due to knowledge and industry awareness or the lack thereof,  experience, and the willingness to devote to education pertaining to the fire service.

 

Granted there are some fairly wide-spread areas doing business the same way they have 20 or 30 years ago simply becouse that is all they know, that's all that has been handed down to them, and all they care to learn. In other words, a tradition of failure to evolve.

Considering the above exceptions, regardless of your level of experteise, without a response time in which you arrive in time to actually make ANY kind of "save"...property or life, and sufficient staff to even consider an offensive, interior attack, you have lost the battle before it began (which is where fire preventions, and even community awareness comes in).

SO, without the resources to get the right line in the right place, secure  a continous water supplyor at least have enough on-board water to make the knock-down, and provide the timely and proper-placed ventilation to support the interior agent application (locate, confine, CONTROL, extinguish) and make a search within the first three minutes or so of arrival (depending upon the size of the structure) there is just about no chance for success to make the stop and the search together.

And so maybe it IS a fact that fire departments are arriving in time to otherwise be successful, excepting that there are only two of them. And there IS no second, third-due engine, or even a first-due truck coming at all from the department, but instead from the next community 5 miles away, maybe ten or fifteen minutes from that first-due, two-person engine. THAT IS reality for more departments than we care to admit!

Should they do nothing? (subscription-based aside) Is it acceptable to take the window, or if already blown, direct a stream through it to try to make a knock-down when the property IS "saveable"? IS there somebody in there? IS there no other way to make the entry, or stop the fire spread from preventing a chance?

 

My point is, what I have to work with on a daily basis and what the next opinion-writer has to work with may be at the extreme opposite ends. And there are many poiints in the middle. I don't think I would have much difficulty with a first-alarm assignment of three and two, with four asses in the seats of each apparatus. Forget what you can do with the best case scenario. Apply what you do, and what you know and subtract 75%, or even 90% of your average resources on a response.

 

Now what are you going to do?

 

Is it wrong?

 

Can you stand up to all the optimum-position critics?

 

No offense, no disrespect. Just food for thought, and another breath into the discussion.

Here's where it's effective and appropriate.

If the fire room is in Pre Flashover condition a short burst is all that might be needed to keep it from flashing over. Immediatly followed by appropriate ventilation. This is called a coordinated attack.

A solid bore hose stream would be best but a straight stream will work. Honestly, if a victim was in this room even before you applied water, is he really a salvageable victim? Probably not.

Now here's the rub. A hose stream applied for any length of time will create a thermal imbalance. This is where the water turns to steam, expands and mixes up the hotter gases higher in the room with the cooler gases below. It is especially problematic with fog streams.

So, if you only momentarily apply a stream to prevent flashover, follow up with ventilation you will not create an environment where the steam expands into another room where salvageable victims may be located.

 

  

rescue vs recovery

extra butter, and I got a thing for peanut M&M's.

In response to your 1.

 

There is zero chance that introducing air into this room will initiate a backdraft.  The fire is flashed over and autovented, it already has an unlimited air supply to support the flashed-over combustion.

 

In response to your 2.

 

This room is flashed over.  There is no significant thermal layering in a flashed over compartment.  Once again, the fire is autovented.  Additional ventilation probably won't help and it might hurt, as it might draw the fire to an unburned area of the structure.

Really?  You take unnecessary risk to the firefighters for a dead body and intentionally destroy evidence by moving a dead body prior to the investigation?

 

How do you justify that?

Check out the Underwriters Laboratory study on ventilation. (google it)  They had interior cameras throughout the structure and their test showed the fire did not get pushed outside the room of origin when hit from the exterior.  They also had temperature sensors...and the readings showed although the heat in the uninvolved areas increased ...it was survivable.  Interesting study check it out-JD

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