Pulsing the Knob

[PhaedrusZen]

This is a shot in the dark, since this is a thread from 1999, but I'm trying to track down Paul Grimwood's "Flashover & Nozzle Techniques". I've tried searching and looking at a variety of resources, including "firetactics.com", but I'm striking out. I also don't see Paul listed as a current member of the forum. Tried the Euro Firefighter website and don't see it listed among the downloads available. Anyone have any suggestions?!

[captnjak]

So since this thread has been resurrected, I have to wonder what guys think about the whole "pulse" thing. I just don't seem to hear much about it these days.
I have some opinions that I'll share if there are any replies.

[HuntPA]

I think it is a very good tactic. But it is also one that requires a lot of discipline and practice. It is pretty easy to either waste water by not pulsing enough or to ruin the atmosphere by injecting too much. For the amount of fire that my department sees, we have decided not to go that way.

Again, sound tactic. It is just one that requires more training, familiarity, and use than what we can ensure.

For the record, we went interior on fires a total of 6 times last year.

[captnjak]

"...or to ruin the atmosphere by injecting too much."

This is the part I don't get. Why are we protecting the atmosphere. The atmosphere is bad. It is dangerous. We go to fires to destroy that atmosphere. Why would we protect it?

Visibility? No. There is no visibility. The smoke "layer" of years ago is extinct. The smoke is thick floor to ceiling.

Thermal layer? Same answer. Our best tactic is to cool the area (and every adjacent area) ASAP. It is the reason we show up. Not to mention the thermal layer is also floor to ceiling.

Reduce steam? No. We can't extinguish a fire without producing steam. Period. Modern encapsulating PPE makes steam little more than a nuisance.

[HuntPA]

We still operate raising the nozzle to the ceiling for a "Z" or "T" pattern and then back to the fire rather than pulsing the nozzle. We try to control the environment without completely upending it. We are looking to cool the upper atmosphere as we cool the fire so at to maintain stabile environment possible.

The majority of fires we are at are already self vented by the time we are dispatched. Even more so when we arrived. They are not in the incipient stage, they are well established and relatively stabile in growth. This is not to say that we haven't been able to stop fires, contain to room and contents, but the fact of the matter is that the majority of our structure fires are barns, sheds, garages, or houses beyond interior operations.

[captnjak]

Not to be a dick but I don't see how cooling the fire area can ever allow for a stable environment. Immediately upon application of water the area cools, smoke production is reduced and production of fire gases is reduced. All good things. The increase in steam is a welcome trade-off. Even without ventilation.
I'm still amazed at how quickly these fires develop to the point of self-venting. Our response times are as good as it gets and we still routinely pull up on self vented fires.

[FyredUp]

Not a fan of pulsing. Smooth bore or straight stream worked floor to ceiling in the fire area has always seemed the best answer to me. With today's black fire waiting to light up I want to thoroughly cool that as I advance.

[captnjak]

"I want to thoroughly cool that as I advance."

I think anything less is literally playing with fire.

We don't need to wait until we get to the immediate fire area. We don't need to hit the base of the fire. Those concepts are downright ancient. Mentioned earlier in this ancient thread back in 1999.

The floor to ceiling nozzle work is a good point. I remember when we were taught that we could locate the area of origin for the fire by looking for the V-pattern of scalding on the wall. At any fire that gets past the incipient stage, there often is no V-pattern. All four walls are often scalded right down to the baseboards. And this is in a department with great response times and staffing. We get water on the fire as quick as anyone. The base of the fire is all around us as we advance. Lots of water applied quickly is the way to go.

[FyredUp]

We don't need to wait until we get to the immediate fire area. We don't need to hit the base of the fire. Those concepts are downright ancient. Mentioned earlier in this ancient thread back in 1999.

I fought this battle over and over and over as an instructor. We would take students into acquired structure training fires and lead them into the fire room to attack the fire. Inevitably dropping smoke, heat, and steam down on them. I started teaching my students to start hitting the fire from the door explaining that the hose stream has 50 to 75 foot reach. The hardest was convincing some of the instructors to change their tactics. Too many started with the bastardized Layman steam fire attack where they crawled into the fire room, nozzle on wide fog and filled the upper atmosphere with steam and dropped all of the black nasty down on top of them. Students, and honestly most firefighters, were pretty open to the idea of hitting the fire from the door.

[VinnieB]

I still think folks overthink this job. Does it work, sure, but like anything it needs parameters. What’s the water supply situation, how much fire, what kind of a building, manpower, etc etc etc. We don’t use it. You get as close as you can and open up and move forward in circular patterns being sure to sweep the floor, once into the fire compartment, you be sure to hit all four corners of the room and keep moving forward till its all out. Visibility will improve with venting, vertically and horizontally and if you are not making progress, check water supply, application, or drop below because it might be below you are in the walls running hard.

[captnjak]

Not sure how manning makes a difference. Same for building type. Once the line is in position to operate those things aren't a factor. It's about the water and it's about the fire.
If water supply limitations dictate water conservation is needed then you probably shouldn't be inside the building.
Getting "as close as you can" is not necessary. I assume you're talking about the area of fire origin. Heat and fire gases will be rapidly spreading to adjacent areas. Water should be applied as soon as we get to THOSE areas, regardless of the area of fire origin.

Great point about possibly dropping below. Any time we think we have the fire located and it turns out to be questionable, the area below MUST be checked. This is routine when staffing levels are high. I almost never get very far into an operation without ensuring the floor below has been checked. Even when things look very "obvious". Because surprises are a bad thing. I am fortunate enough to have great response times and great staffing. But even with lower levels of staffing we have to be sure that fully confirming the location(s) of fire is a priority.

[FyredUp]

Getting as close as you can should be replaced with getting as close as necessary to effect fire attack. There is zero need to crawl into a room full of fire without hitting it first from the doorway and knocking down as much as possible before entering to finalize extinguishment. Obviously we may have to hit fire in the hallway, or the overhead as we advance, The reach of a fire stream, whether smoothbore or combo on straight stream, is between 50 and 70 plus feet, we do not need to lay on top of the fire to hit it.