3-D Firefighting on PBS

[kprsn1]

Many of you recall Paul Grimwood and his teachings and discussion regarding tactics and 3-D firefighting. A program on PBS, Wired Science, will air a segment, I believe on Wednesday night, that discusses the 3-D firefighting technique. Wired Science

[medic563]

If you miss it I believe it becomes available online after it airs

[Bones42]

Quick, someone PM Batt18, he might be interested in this.

[backsteprescue123]

Thanks!!!!!!!!!!!!!

[NWOhio157]

http://www.pbs.org/kcet/wiredscience...-fired_up.html

BUMP.
So after watching, what does everyone think about the new ideas?

[cowbucks06]

They neglect to mention that 3-D really only works on small enclosed spaces. High vaulted ceilings common in modern American construction would require that the stream be constantly readjusted. The PPV attack is one of the better ideas shown.

And DFD doesn't really have the cooler chairs. That was basically a promo spot for Total Fire Group.

[mcaldwell]

PPV and 3D FF'ing in the same bit? This thread itself might explode at any moment.

[DeputyMarshal]

The 3D segment was interesting but I'm wondering why this technique that I was taught some 25 years ago under the general heading of "indirect fire attack" has somehow now just been invented in England & Sweden...

Not that it isn't a perfectly useful and effective technique when used correctly but is our institutional memory really so short that we actually think something is "new" when it's repackaged and reintroduced to a new generation?

(Ditto PPV: It's hardly a "new" technique...)

[ChicagoFF]

The 3D segment was interesting but I'm wondering why this technique that I was taught some 25 years ago under the general heading of "indirect fire attack" has somehow now just been invented in England & Sweden...

Not that it isn't a perfectly useful and effective technique when used correctly but is our institutional memory really so short that we actually think something is "new" when it's repackaged and reintroduced to a new generation?

(Ditto PPV: It's hardly a "new" technique...)

Kinda like ICS, huh?

[ChicagoFF]

They neglect to mention that 3-D really only works on small enclosed spaces. High vaulted ceilings common in modern American construction would require that the stream be constantly readjusted. The PPV attack is one of the better ideas shown.

How about just going in and putting the fire out? That's my favorite "technique"...

[Edward Hartin]

The posts on the Wired Science show raise a number of good points but are in some cases based on misconceptions about 3D firefighting tactics. When I watched it I reminded myself that the target audience for this show is people interested in innovations in technology. It was not a fire department training program.

Not included in the show was the discussion of exactly what the 3D concept is all about (less interesting to the producer and audience than flames and smoke). It is not simply gas cooling with pulsed water fog. First and foremost it is recognition of the three-dimensional nature of the fire environment (obvious, but often overlooked). Second is development of a solid understanding of both the theory and practical aspects of fire behavior and fire dynamics. Third, is control of the fire environment through the use of a full set of fire control tactics (such as gas cooling, direct attack, and indirect attack) along with ventilation and confinement tactics. This is not "new", but places understanding of fire behavior at the center of the training process.

PPV was also presented as a "new" technique. Not so... Positive pressure ventilation was first explored in Germany in the 1950s, but rediscovered in the US many years later. What is new is understanding of how PPV works from a scientific perspective (as in the work being done by NIST). As with many other tools and tactics in our craft there are many people who do not have a solid understanding of how positive pressure ventilation works, its capabilities and even more important, its hazards and limitations.

cowbucks06: Gas cooling does not only work in small enclosed spaces. While there are limits on compartment size, this technique works quite will in the compartments of sizes found in most residential and many commercial occupancies. You are correct that the stream may need to be adjusted as based on the size and configuration of the compartment, but this presents little problem.

mcaldwell: Good point that concepts are often recycled. I also learned a variation on gas cooling (which was referred to by the instructors as "indirect attack") early in my career as well. However, this technique was considerably different than the application of gas cooling pioneered by the Swedes in the 1980s. In addition, indirect attack (as outlined by Lloyd Layman) is an even more distant cousin of 3D gas cooling. Indirect attack (as outlined by Layman) involved cooling and displacement of oxygen by filling the space with steam. The "indirect" method that was commonly taught in the mid 1970s was used to control rollover with brief application of water fog. 3D gas cooling on the other hand involves several things, first is cooling the hot gas layer (without disrupting the thermal balance) with extremely short pulses of water fog, second is use of pulsed application to control flaming combustion overhead. These are not extinguishing techniques, but simply a way to control the hazards presented by the fire environment while gaining access to shielded fires.

ChicagoFF: Getting in there and putting the fire out is exactly the point. However, extreme fire behavior presents a significant threat (20 firefighters in North America have died from one form of extreme fire behavior or another since the first of the year). While I am not suggesting that gas cooling in and of itself would have prevented these deaths, an improved understanding of fire behavior, recognition of critical fire behavior indicators, and effective integration of fire control and ventilation tactics can significantly improve our safety while working in burning buildings.

Cheers,

[BLSboy]

Ed, several items for you;

First and foremost, thanks for taking to time to try out new methods, and try to change the culture here.

Now, I am a tad confused as to the actual methods of this mode of fire attack. You "just" cool the upper layers of the gasses to prevent rapid fire development, or you use this as a method to actually extinguish the fire?
Also, how compatible is the method of attach with PPV?

While this does look interesting, without a qualified instructor to teach it around here, I will be sticking with popping the back door, throwing PPV in the front, going to the fire, and knocking it down that way.
I am not going to try fancy stuff unless my crew, as well as myself, know its ups and down, inside and out.

[PureAdrenalin]

How does that saying go? "speed and water always work?" Yeah..I think that's it.

[Edward Hartin]

BLSBoy,

The layer of hot smoke overhead consists largely of flammable products of incomplete combustion and pyrolysis products. 3D gas cooling involves application of short (really short) pulses of water fog into the hot gas layer to reduce its temperature and introduce moisture as thermal ballast that slows reheating of the gases. Pulsed application reduces the potential that this fuel will ignite, resulting in extreme fire behavior. Pulses are applied as the crew moves from the point of entry to a point where a direct attack can be made on the fire with a straight stream.
The use of gas cooling can be readily integrated with positive pressure ventilation. Where PPV is used, the short pulses cool any residual gases and moisture are carried towards the fire, continuing the cooling process. Where PPV is inappropriate, gas cooling provides additional protection for the hose team moving in on a shielded fire.
There is a bit more to this than simply cooling the gases. It is also important to think about the effect of tactics on fire behavior and coordination of ventilation and fire attack (particularly with PPV). Good “old school” tactics, but often overlooked.

PureAdrenalin makes a good point that speed and water work. Water applied in the right place sooner rather than later generally provides a more positive outcome. While it might seem that cooling the gases as you move forward under the hot gas layer takes time, a skilled nozzle operator will likely move almost as quickly as if they were not cooling the gases. However, it is also important to assess conditions and not move so fast that we fail to size-up conditions and maintain situational awareness.

Cheers,

[BLSboy]

Ed, to a lesser degree, would "pencilling" have the same effect? We are in the process of switching to combo nozzles, and the plan is to take the tip off, using the smoothbore for direct attack, then using the fog tip for overhaul, and hydrolic ventilation.
That being said, I do not know how much time it would take to spin the tip off, exposing the smoothbore tip.

Finally, is this something that can be used by joe schmo Fireman? I saw in the video that the nozzleman was just quickly opening and shutting the bale of the nozzle, for maybe, .5 seconds at a time, on various times. I know not to go in on full fog aimed up, until I reach the fire.
I have several live burns coming up, and this is the kind of thing I would like to experiment with the determine, for myself, its effectiveness.

[Edward Hartin]

BLSboy,

Penciling the ceiling does provide some cooling overhead. However, a solid or straight stream has less surface area and is less efficient at absorbing heat as it passes through the hot gas layer. This makes it more effective for direct attack (most of the water goes to the burning fuel), but less so if you simply want to cool the gases overhead.

We use dual pressure (100 & 50 psi) break apart automatic nozzles with an integrated solid stream tip (15/16”). This provides a high degree of flexibility, but our guys find that the combination tip works well in most situations without switching pressure mode or removing the automatic to use the solid stream. Regardless of what type of nozzle you have, it is essential that the nozzle operator knows how it works! At the risk of stirring things up, I would use the combination nozzle all the time (reach and penetration is not generally a major problem when working inside most buildings), reserving the solid stream tip for situations requiring a lower nozzle pressure or greater penetration.

The issue of “can this be done by the average firefighter” is often raised in discussion. My answer is absolutely! It is more difficult to figure it out than learn it from someone who has already developed the skill, but this is being taught all over the world and is being used by “average firefighters”.
The angle of the fog pattern and duration of pulses is dependent on the space you are working in. Generally we start with a 40 degree pattern and extremely short pulses (imagine the fastest you can open and close the nozzle and do it just a bit faster). How this is accomplished depends on the nozzle you are using. With automatics, you can open the nozzle part way and still have an effective fog pattern (at a reduced flow rate). This makes it simple to apply low flow pulses to cool smoke and a high flow direct attack to extinguish the fire. With fixed flow nozzles, you may need to open the nozzle fully (increasing the need for quick hands in opening and closing the nozzle). An important not here is that there is a limitation on flow rate. We use short pulses when the hoseline is pumped for a maximum flow of 150 gpm, if the hoseline is being pumped for over that flow rate we only use long pulses (open quick and close slowly). One way you can experiment with this outside the fire environment is to see how long the water fog hangs in the air. If the majority of the droplets hand for 4 or 5 seconds the pattern is ideal.

When teaching this, we start out simple and progress from there. First the learner observes, second operates the nozzle from a fixed position to observe the effect of pulsed water fog on the hot gas layer and fire development along with the effect of the straight stream on the fire and pyrolyzing fuel, and last development of skill in application while advancing and retreating.
Many people are teaching some form of this technique as part of “flashover training”. What is different in a 3D firefighting context is that we want to control the environment to as great an extent possible to prevent flashover (or other extreme fire behavior) conditions from developing or if that is not possible, to avoid placing ourselves in a position where we may be injured or killed by rapid fire progression.

If you are interested in learning more, contact me off line and I can point you to some other resources.

Cheers,

[kprsn1]

Ed, thanks for the insightful look at the 3-D technique. Are you sure you're not Paul? My take on this technique is very simple from an educational point of view. If I can add one more system or technique to my arsenal of weapons for fighting fire then so be it. Would I use 3-D firefighting in EVERY fire I fight, no, I'm sure I wouldn't, but for that one time out of 100 when I can recognize the conditions of an impending fire event and utilize the pulse method then it's well worth learning about. Learning this method just gives me another option when sizing up my stragegy of fire attack.

[Edward Hartin]

kprsn1,

I don't think that I would be confused with my brother from the UK (I have a bit more hair).

While gas cooling is not always necessary, it is important to recognize that this is not simply an approach that is used when flashover or other extreme fire behavior is imminent. Gas cooling should be used (along with other tactics) to manage the fire environment before you get to that point!

Cheers,

Ed

[Batt18]

kprsn1,

I don't think that I would be confused with my brother from the UK (I have a bit more hair).

Cheers,

Ed

......... and Grimwood is also much better looking

[Batt18]

Would I use 3-D firefighting in EVERY fire I fight, no, I'm sure I wouldn't, but for that one time out of 100 when I can recognize the conditions of an impending fire event and utilize the pulse method then it's well worth learning about.

Hey Kprsn1 ... this is Paul Good to see you followed the program.

I would just add that 3D Firefighting concepts are ideally followed at EVERY working fire and not just one in a hundred. Remember that we are talking fire behavior; tactical venting actions; fire isolation (anti-ventilation) in some circumstances; pulsed and bursts of water-fog sure .... but primarily an essential feature of our training program is safe and effective entry to the structure/compartment. We use a 'door entry' procedure to counter situations commonly encountered as follows ... Quite simply, if we suspect there may be smoke, heat or rollover behind a door we try to prevent any auto-ignition of the gas layers or backdraft of the fire, as we open up to advance inwards .... maintaining control of the situation is the objective .... www.firetactics.com