Coordinated Vertical Ventilation (Arrival, Cut, Aftermath)

(Note: Brian Brush and myself were having a discussion early this morning about these photos. They are some of the better photos I have seen in a long time showing vertical ventilation in coordination with an interior attack. Rarely do we get photos that give you an accurate look of the building upon arrival, as the lines are being stretched, the hole being cut, the smoke lifting and the vent hole igniting, and then wrapping it up with a great photo as the engine makes a hit on the fire. We both thought it was worthy of discussion and definitely photos worth sharing with everyone for their own vertical vent training. I provided Brian with the photos and some of the on scene tactics and he put the article together for us. Thanks Brush!     – Ryan Royal)

Let us first begin with a review of what UL is saying, not from my interpretation but from the source themselves. UL exists to present data not dictate tactics. As you can see from the list presented in the slide to the left from their presentation they feel there is a need to clearly address several points which some in the fire service are misinterpreting, one of which is vertical ventilation.

Image 9

From what I have gathered from the UL studies and presentation of their data there are several key points.

-Fires in enclosed structures are ventilation controlled

-Ventilation will intensify fire behavior

-Ventilation must be performed in a timely and coordinated manner in order to be effective and not counter productive

Heat is a fire’s greatest strength and most predictable attribute, it wants to go up. Using the thermal column to ventilate fires has allowed us to live and work around fires in enclosed spaces for thousands of years. Because of the simplicity and reliability of the chimney effect, using heat to ventilate should be the first option considered. Vertically venting also takes a great deal of the fire’s energy out of our plane of operation as we typically operate horizontally in structures with our stretches and searches.

There are a few key problems with utilizing heat as a ventilation method on most fires. The first is that unless it is a top floor fire the opportunity to get over the fire is not as readily available as horizontal options (windows and doors). The second is that once on the roof an opening must be created using saws which causes “damage”.

Aside from these two physical factors there is an overwhelming mental limitation to the utilization of vertical ventilation. The first limitation is the fear of working over fire. Be it searching the floor above for VES or vertically venting there is an almost instantaneous reduction in acceptance of the tactic due to “risk”. The thing is that many times between the roof decking and the room you have the compartment of the attic as a buffer. Too often this is lost on people who are predisposed to critique the viability of the tactic.

Image 8

In the first picture the hole in the decking has been cut and the smoke pushing is from a charged but uninvolved attic space. At this point no structural members of that roof are being exposed to fire however within the compartment of the top floor of the residence a significant fire is working and filling out the occupancy with smoke and heat. You can see the firefighter punching in the lid of the room with his pike pole which drops the ceiling and vents the room up and out. In the picture to the right you now see “heavy fire” but the lack of smoke displays a clean burn.  At this point the fire is impacting structural members of the attic space but the operation is complete and firefighters are off the roof. In many vertical ventilation scenarios the “10 minute ticker” of light weight construction isn’t started until firefighters have executed their mission which allows plenty of time for suppression.

The second mental limitation is the lack of confidence that vertical ventilation can be executed in a timely enough fashion to be coordinated. Working with ladders takes practice to get proficient but in this proficiency you will find the quickest route to efficiency as 80% of the time it take to preform vertical ventilation is getting to the objective. Quickly performing vertical ventilation also takes a game plan, rehearsal and even choreography all of which are barriers but none of which cannot be overcome.

As with anything there are no absolutes. You may be working in a department where getting one company to the scene to stretch a line in a timely manner is a problem let alone two companies arriving together to work in a coordinated manner. But for many of you I think it is important to note that with practice, training and understanding, many suburban districts where two companies are arriving in close proximity, will have 1 and 2 story single family dwellings that have roofs accessible by standard ground ladder compliments allowing for coordinated vertical ventilation as an option.

This series of pictures is from Colorado Springs Fire Department. CSFD sends 2 engines and 2 trucks to a single family home 1st alarm.  This is a midsize department consisting of 21 Engine Co’s, 6 Truck Co’s and a Rescue Co for a population of about 500,000 people. They serve everything from urban areas, suburban neighborhoods to urban interfaces. Do not get lost in who CSFD is and focus on this residence and the fact that three essential fire ground operations are being executed in coordination by the first two companies.

Image 5 - Version 2

This first picture is just after arrival of Engine 8 and Truck 8. While E8 is stretching across the yard T8 Irons crew will assess forcible entry and prepare to search and T8 ladders crew is the team going to the roof. You can see how charged the occupancy is with smoke pushing from eaves around the entire structure.

Once teams make entry on this type of fire, the conditions interior will confirm one of two things from what is observed on the outside. The fire is an involved compartment fire that has difficult conditions interior and is also pressurizing the attic. Or we will find that conditions interior are showing light to moderate smoke with no obvious fire and at that point we should be considering strictly an attic fire, or an outside fire that is moving in. Which this specific fire was.

Multiple ladders are thrown and access is made to the area suspected to be closest to the fire. This was determined by smoke conditions of the eves and of the roof vents near the ridge line. Access to the cutting area is done utilizing the hip of the roof for stability and using your hook to provide solid sounding of the roof decking. Once at the ridge a roof survey can be quickly visualized to confirm fire location and roof stability.

Image

Once the position was chosen, the roof decking is cut and  the charged attic space dumps very pressurized smoke out of the opening.

Image 2 Image 1

The smoke quickly ignites, a thermal column develops and is intensifying the fire but increased fire activity and energy is largely channeled up and out.

Image 6 - Version 2

You can see in this picture the overall presentation of the structure is cleaned up and you have free burning out the vent hole. Less than a minute after the hole is cut T8 ladders crew is on the ground.

Image 7

Shortly after that E8 now has very clear access and an obvious fire location above them, they pull ceiling from below and hit the fire in the attic. The steam conversion is observed as it too is now channeled up and out the vent opening. This is about as text book an example of coordinated vertical ventilation as you can find. Executed largely on a foundation of clear expectations, solid understanding, and constant training.

IMG_1180

The take home here is that while CSFD potentially has a bigger first alarm assignment than your district this was handled largely by 8 people. While T8 is a 109’ aerial, this was executed with a chainsaw and a ladder compliment found as standard on most all engines in smaller departments.

Stop letting people tell you what you can’t do and start looking at what can be done.

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24 Comments on “Coordinated Vertical Ventilation (Arrival, Cut, Aftermath)”

  1. Rodgers Says:

    Great job and write up!

  2. GaryLane Says:

    Perfect.

  3. Boltz Says:

    I would strongly disagree that this is ‘coordinated’ ventilation as it is intended to be in todays modern (educated in fire dynamics fundamentals) firefighting context. The fact that the whole team was on the ground prior to steam exiting ( fire attack being successful) shows there was a considerable delay between the vent team opening the roof and ceiling, until water was applied. I would think that at least (at absolute minimum) it took the vent time one minute to get off the roof. This is one minute ( again perhaps 2 or 3 minutes) or fresh air entraining to the fire as the hot fire gases are removed(conservation of mass) from the structure. As most of us know this oxygen would have rapidly increased the fires heat release rate due to it being a ventilation limited fire. So, had the interior crew taken a wrong turn, or not have been able to suppress the fire AFTER vertical ventilation was made, this could have potentially turned out much much worse.

    This video below, shows great work and patience being performed by the FDNY at a recent fire. This is what ‘coordinated’ should be. No vent made until water is on the fire, or at very least, until the interior has located the fire and has communicated they are about to begin attack and for the vent time to proceed.


    • Boltz,

      That is an interesting point of view, I do agree with the video you posted being a fantastic example of coordinated attack with horizontal ventilation. But these are two fires in very different locations of a building. The photos that are in the above article is showing an attic fire that was from a fire in the wall/outside that moved in. Crews were in place with a charged hoseline very close to the base of the fire, but not able to fully locate it until the vent was performed. I think the assumption that “water on the fire took a considerable amount of time” is slightly off base. After the vent, fire did light off, but channeled everything up and out of the enclosed attic. I am curious, would you rather this come down on the interior crews? Or are you saying your department has the roof team wait on the roof until an interior crew hits the fire and then you vertically ventilate? I’d like to hear more. Also whats your name? Hate using nicknames in conversations like this.
      Thanks for commenting
      Ryan Royal

    • Johnny Says:

      Stopping lateral spread is the objective. If the heat increases, but the fire is channeled up and out of the building (along with the smoke), it’s going to be an easier attack. Advancing through a house requires opening a vent hole. That’s how we get in. It’s unavoidable. If the fire doesn’t have another way out, it’s coming for that opening. Smoke and heat will be banked down and will have lateral spread. That’s reality, that’s experience. The hole makes the advance easier, and the easier the advance, the quicker the water hits the fire.

  4. Manny Says:

    We started from scratch in the mid 90s to bring Truck OPS to Colorado Springs. I could not be prouder of the work of the members of the Springs firefighters. National recognition way to go
    .

    For those that need further justification for 4 person fire companies, look closely at these photos.


    • This video doesn’t really reinforce your point that the fire burned unchecked for a long amount of time after the hole was opened. You can see the second firefighter that just opened that hole getting on to the tip of the ground ladder in the video. They just finished vertical vent when that video was started.
      Ryan Royal

    • Ian Bruzenak Says:

      There was no delay in direct decisive delivery of water (Nozzle Forward).

      Ian
      Station 8

  5. Bryan Lynch Says:

    Interesting discussion. My name is Bryan Lynch and I was the engineer for the first due company (E8). I respect your point of view Boltz but I must disagree. This was a textbook example of coordinated fire attack. The conditions for vertical ventilation were perfect. Outside fire that burned into the attic and a well involved attic fire with heavy smoke issuing from the eaves on all sides of the structure. First hoseline stretches interior and was met with moderate smoke conditions. While the line was being stretched, the vent team proceeded quickly to the roof and made a hole. As someone who witnessed the events unfold I can say without reservation that the time between the roof being opened and water being applied was less than 60 seconds. It’s difficult to tell from a serious of pictures the absolute specifics and circumstances regarding a fire like this. No fire attack is going to be timed perfectly with ventilation. The success of this fire rests solely on the first due companies and their mentality.

  6. Ian Bruzenak Says:

    Boltz,

    The engine crew was advancing into te building with door control being used. From the moment the roof was opened the hole was a 100% unidirectional exhaust opening. The engine crew had nothing come down on them (pressure from the exhaust side of the pump/fire) I was all exiting through the topside hole. That means that all the good air bein pulled into the pump was from the lower openings replacing the occupied space with good air…. The cat chilled in the living room through the entire fire. I consider myself very well versed in the recent (10 ish years) of NIST and UL studies. This was coordinated.

    Ian
    Station 8

  7. Tim Nemmers Says:

    Let me open by saying good job.
    I would be proud to be apart of that incident.

    For the sake of debate & education-
    First, Look at the amount of snow melt that occurs, on the shingles, in the area under and around the vent opening, before, during, and after the vert vent occurs.
    It would indicate temps rise in the low levels of the attic.
    After the “Uni-directional flow path” establishes the thermal flow- up & out.

    Second, I believe Boltz is trying to illustrate that a “near” perfect coordination would be to have the cut in place, but hold the louver and ceiling punch until energy control (water to steam) is driving down the compartments temps, then open the attic/vert vent.

    Or to say it another way- keep the box closed until water is flowing & converting.

    Lastly, I might guess that the flame is burning exterior, but the attic might still be lean, or o2 deprived, initially when the vent opens.

    Again, I am not knocking, I am discussing.


    • Thanks for discussing Tim, I will hit on a couple of points and maybe the other guys that were there will want to chime in also. The photos do show the snow melt as the attic begins to heat up and then fully vents. You can even visualize the truss spacing because of the decking heat. I know these guys cut the hole and got right down, which in this case was a good call. They already had fire in the attic and weakened decking in some areas that they identified with proper sounding and visual indications.

      You mention Boltz point, and I get what your saying as far as fire advancement due to the vent being opened, but at the same time as long as a hose line is in place I don’t see the downfall of opening it beforehand. I do agree with closely coordinating it, but why not open it up before? This lifts the conditions to allow the engine to quickly hit it and prevents any of the ignition that happened up and out from being ignition that happens horizontal inside.

      For discussions sake (it doesn’t really apply to the fire in the article) If someone was to do what your saying as far as waiting on the roof and not opening until the engine knocks the fire, how long do you wait? If the engine is having trouble locating do you remain in the holding position on the roof? Because your holding the key to assisting them on the inside with what they may be struggling with.

      Thanks
      Ryan Royal

      • Tim Nemmers Says:

        If there is a fire in the attic do you still have the roof team drop the top floor ceiling?
        (Why wait) Once the vent is open it’s not reversible. If your line has kinks or a debris you have already started the increased HRR on a ventilation-limited package.
        (Downfall) in this scenario, I agree, the margin was wider. As I said, and meant, I would be proud of the work. However, you get a big house, or large building, with line stretch issues, or water delays – will they ask? Will they wait. Will they look for signs in the lack of comms? Is it a habit or is it a decision?
        I am not knocking this crew. I am simply discussing firefighters in general.
        (How long) Wait as long as it takes. How long does the OVM wait on the stairwell?
        (Additionally) I am an advocate of sequential ventilation. If I was a truck boss on a similar fire, once the plume of solid white steam rose, I would consider calling for a PPV, from the inside team. Adding a hydraulic vent up the vent hole for a few moments as well.


      • Tim,
        Appreciate the thought out discussion, nothing taken personally here, I enjoy talking shop with different opinions.
        About the roof team dropping the ceiling, I think that will vary. This fire for instance I would say no. The fire almost immediately ignited out of the vent hole and the interior crew immediately saw a glow from below through the drywall seams. I think you get off the roof at that point. I think there’s situations where you drop the ceiling when you cut even though you were thinking it was an attic fire. If they don’t get the production they wanted possibly indicating that is has not worked its way into the attic but it is close to it, or based on conditions, etc. I agree once we vent we have changed the game and should be attacking soon after. The engine potentially having kinks or debris is something we risk on every fire and it is difficult to base our tactics off of those possibly happening. Even without vertical, if those problems happen we must quickly fix the problem or the interior could become just as dangerous as that happening during a vertical vent operation.
        Your points about what a roof team should be paying attention to as far as building size, conditions, communications and so on, are all very valid points. I think a crew venting a flat roof over a commercial will be up there much longer than a crew venting a lightweight rancher. Is it a habit or a decision is a good question and something we have to all self evaluate and remind ourselves.
        When your talking about the Outside Vent Man waiting on the stairwell, I agree he can and should wait as long as it takes, that earlier video was a great example of OVM discipline and good timing. I don’t know if I agree with a roof team on a 1/2″ plywood deck waiting for as long as an OVM has on an exterior stairwell. Especially if it is an attic fire and not a contents fire that we are going to knock ceiling down to. The damage below us as already begun with our attic fires. As long as the engine is advancing, charged and ready to attack (without special circumstances like size, delays, etc), I think us getting up, cutting and getting down is what makes this a solid tactic that is sometimes made to sound more dangerous (on LW construction) then it needs to be.
        Thanks
        Ryan

  8. Brian Brush Says:

    I work with a close knit well trained crew and we find it difficult to coordinate at the grocery store.

    The fire scene is dynamic, radio communication is less than perfect and we are firefighters. This is truly about as good as you could possibly see lay out on a true emergency scene. Once again I think there is good stuff in debate but be realistic in your frame of view.

    The one point I will add is that this fire is confined to the compartment of the attic. Any puncture of that compartment is “ventilation” as the compartment is a high pressure space with hot gases and byproducts of incomplete ventilation limited combustion charging that space. To pull ceiling and get a line in place on the interior of the residence before venting the attic compartment to the exterior would develop a flow path into the very occupancy we are trying to protect from damage (counterproductive). Opening the louver and using convective currents to develop a thermal column at the same time reducing the pressure of that space make the potential for you to pull ceiling and not have a dump of heat or smoke into that occupancy that much better

    • Ian Says:

      There are two ways to remove the energy from the structure. One – water or other agent. Two – ventilation allowing the energy to leave the structure. Using one without the other is like tying a hand behind your back for a fight. I can not buy off on that concept.
      As the fire is ventilation limited the oxygen concentration drops very low very fast. Vertical Ventilation with suppression is the fastest way to remove the energy and restore oxygen levels.
      If a engine company was to make a wrong turn and go down the hall to the bravo side of the structure turn around or flow back behind them, that action alone would drop temps throughout the structure and “reset” the fire. Allowing for the engine to reposition.
      As far as dropping the ceiling. There has to be a thinking part to what we do. What space are we venting? Why are we venting? While making my way to the roof sounding and observing an attic vent on the backside of the roof pushing smoke, made a decision to only vent the attic space. Knowing the energy being produced by the obvious attic fire, I did not want to take the barrier between the engine crew and the pump/fire. I leave that to them to get in place and be ready. We cut the hole, got off the roof and went directly inside to help. We went I to the garage where the engine had pulled ceiling and was extinguishing the fire in the clearest atmosphere I have ever seen.

  9. Mick Mayers Says:

    I enjoyed this article and agree with your premise. Admittedly, I did not look at the videos because really, unless someone has staged the “perfect event” sometimes even using what is “close” to what you are trying to illustrate gets lost in something else on the video. It really does concern me that we have so many in our business that have too, like society, reduced their knowledge base to a few sound bites. Just as a paramedic knows how better to treat a patient if they understand the body and how each system works together, a firefighter must not simply fall upon one cookbook method or approach to fighting fire. The UL study gave us amazing insight into the myths and truths. All this did, though, was reinforce some things some of us have been doing for years, and confuse those who don’t understand firefighting to begin with. No one tool will handle each and every single fire. Sometimes we must vent vertically, sometimes horizontally, sometimes it needs to wait a little. Sometimes we need to attack the fire directly, sometimes we need to put our resources into VES first, sometimes we may have to dig it out. Sometimes we need to step back and say, “Why do we have this need to fight anything that sounds like it may be logical, simply because it conflicts with our own currently held beliefs?” Open up your minds, brothers- use the right tool for the job. Don’t get locked into one way of doing things because of ego or pride.

  10. Tim Nemmers Says:

    Ian, Does Ventilation removed heat from a ventilation-limited fire, that has progressed into a decay/smoldering phase?

    This UL video illustrates the two 7x7ft openings. Does the one on the right allow heat to escape, making it a “fuel-limited” fire?
    Or does it allow the HRR to grow?
    Even with a 49sqft hole, the neutral plane lowers.

    Now, my comparison is this video, the ventilation is limited, and the temps decrease. They shut the door.

    BB, I am not advocating hooking a “big” hole, prior to energy control.
    I am advocate the engine’s version of a kerf cut. Open a small hole, take a peak, apply some water, absorb some heat…. And perhaps move closer to the seat if required.

    BB, I use this as a learning tool. Don’t open the ceiling until your have good water. You open a small hole, apply water. Then move closer to the seat, or enlarge the hole, apply more water.
    IMO, once your Lineboss thinks you’re “in the spot” & flowing, call for the louver.

    Now compare how well this vid is venting-http://www.youtube.com/watch?v=zdBDMFHsdnA&feature=youtu.be

    Increase exhaust ventilation – increase speed or amount/volume at the intake. Limit the exhaust, in turn limits the volume at the intake.
    Think of a turbo diesel & how the turbo lag is over come via the intake.
    Or your weber charcoal grill. The intakes (side vents) can be open. But it is the top vent that controls the “thermal throttle” Open the top, temps increase. Creating an efficient thermal flow(path).

    RR, I concur, the sheeting is the weak point. Can this be delayed via roof ladder usage? Can this be prolonged by venting away from the origin (while the hole remains in the same compartment/attic)? As the delay is prolonged could the aerial’s main be swung for the crew to have refuge while waiting to open the louver? Perhaps not, to all….

    BB, I concur it is complicated communication. It may not happen. But should it be discussed? Maybe not.

    But as the author RR stated, “Stop letting people tell you what you can’t do and start looking at what can be done.”— Is the reason why I ventured into the discussion.

    In full disclosure, it is not happening in my FD. But I continue to pose the question, debate, & learn from others.
    Thanks for the feedback.

  11. Tim Nemmers Says:

    Here is an example of what I am attempting to express, “Why ventilation opening should occur after water is applied (seconds).”

    Quote,
    ‘Both good questions! As previously discussed, smoke discharge (as well as movement on the interior) is the result of both differences in pressure and density. If considered simply from the perspective of higher pressure on the interior, smoke would discharge from the building until pressure equilibrium is reached (with the same pressure inside the building as outside). This is related to exchange of mass and energy, but only indirectly. If you opened a cylinder of compressed air, air would be discharged out of the cylinder into the atmosphere (no exchange). However, with a fire burning in the building, air must flow inward to sustain release of thermal energy, which in turn maintains (or increases) the temperature that causes the pressure increase.”

    ^ From here: http://cfbt-us.com/wordpress/?p=2000
    After “Mike Asks:” (in bold)

    “As air, products of combustion, and pyrolizate are heated, the volume increases (but mass stays the same), cooler outside air flowing into the building is more dense (smaller volume, but the same mass). This results in approximate balance between of the mass of hot air and products of combustion exiting the building and the mass of cooler external air entering the building.”

  12. Bob Ryner Says:

    Tim, absolutely great words. It is often clear to me when reading peoples comments to the degree of fire dynamics, thermodynamics, fluid dynamics education they have. Often people limit their reading to the UL & NIST material, picking up a few copies of fire magazines and that its. If firefighters really want to debate fire dynamics/behaviour and ventilation, and really understand it, we need to branch out and dig deep. We should know what Charle’s, Boyle, and Guy-Lussac’s Gas Laws are, know who Drysdale, Quinteire and Thornton are, and read and study their material.

    As important of information UL and NIST is giving us, they are leaving lots of room for interpretation when if comes to tactics. This then remains in the hands of FF’s to decide what ‘coordinated’ means for example. And when FFs try to do this, and don’t quite understand how a fluid mass within a closed or open system behaves, what 13.1 Mj/kg of O2 means to fire development, it is somewhat difficult to have people really get the most out of these various research projects.

    But, no doubt this crew did a great job. But the debate is really about ‘was it done as safety and effectively as possible’. That is where we are at here. If fire crews increase the HRR upon implementing fire ground tactics, then IMHO, the objective was not met as effectively as possible. However, not to say overall it was not successful, This was. The fire went out, everyone went home safe (VERY IMPORTANT), but again was it as effective as it could be? Maybe , maybe not..

    I would like to commend this crew for their work. Well done! My words are really about the BIG PICTURE, and our fire service in general. But look at us, we’re all engaging in productive, thought provoking discussions all in the attempt to share our opinons in hopes of furthering the progress of our service. Good work gentlemen!!


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