By Lt. Billy Greenwood – Original Post at: http://community.fireengineering.com/m/blogpost?id=1219672%3ABlogPost%3A589083
We all know that in competitive sports, second place is the first loser. Athletes (amateur or professional) all seek to win the big game. They put in the time, effort and training. The greater the commitment before the game, the better chance you have to be on top of your game! So why should the fire service be any different? Our playing field is competitive and on game day it takes proficient and effective teamwork to mitigate the emergency. Which leads to the point of this article. With the fire ground constantly changing, (lightweight building construction, plastic and synthetic based fuels, and limited manpower) have you remained fireground aggressive from your “past training” and life experiences (or) have you attempted to remain up to date with the modern times as “educated-aggressive”
FETC Services recently conducted a NFPA 1403 live fire training exercise in an acquired structure. Throughout the day we were able to conduct (10) interior fire evolutions. For the final evolution, we completed a real-world fire behavior, flow path and flame spread evolution. The test dwelling was a 3 bedroom; 2 bath open concept contemporary style, single family residence with an attached garage. The weather was perfect for a burn; sunny and 54 degrees F with no significant wind concerns. For many of the participants, this training provided valuable insight on how and why we here at FETC Services feel, many firefighters are getting burned during rapid fire increase situations.
The following photos are property of K. Horgan and J. Sangermano of the Dublin, NH Fire Department; and they documented some significant fire behavior in relation to (VC) Ventilation Controlled vs. Non-Controlled flow paths.
Photo 1. (above) Deputy Chief Sangermano is taking up an interior position in the living room as the kitchen in our test dwelling flashes over. Take note at the time of the kitchen flashover, the side C kitchen window auto-ventilated due to the high heat conditions as seen through the walk-out slider.
Photo 2. (above) The interior crews located in the living room area were evacuated approximately 90 seconds after the kitchen flashover occurred. Through the use of FETC (TIR) Thermal Insult Recognition class, members identified that their PPE had reached maximum heat saturation. Note the crews closed the front door post evacuation and the fire becomes ventilation controlled.
Photo 3. (above) FETC Services Instructor Greenwood is seen confirming accountability (PAR) of all interior crews and was the last firefighter out as the kitchen fire rapidly expands into the living room. The LR quickly became untenable for all participants.
In Photo 4. (left) The front door remains closed and intact. “The Box” has become oxygen deficient and ventilation limited. Note the smoke profile from the roof ventilation holes producing VOLUME and VELOCITY. The third factor in the smoke profile would be COLOR. During this NFPA 1403 training evolution the smoke color will not depict real world smoke profiling due to the Class A fuel source.
FETC NUGGET is contained within this photo. The box has become clearly oxygen deficient. We know we have a kitchen fire depicted in (pic 1) At this point, the fire begins to reduce in size and speed of spread due to the box becoming rich from the ventilation limited environment. (door control) As seen in the above picture, the front door remains intact but the small amount of fire above the entry door should be alarming to the “Educated-Aggressive” firefighter. This is a red flag warning that the box is waiting for well intentioned firefighters to enter and create the needed flow path for rapid fire increase. Now unlike classic textbook signs of oxygen deficient environments AKA backdraft conditions (like puffing smoke; or dark stained windows) today’s firefighter who makes an aggressive entry in these conditions to search for the seat of the fire or potential victims, have a very small window to operate within tenable conditions. Our PPE will provide minimal exposure time protection in these super heated environments. Without a change in fire dynamics, (one example being the transitional attack) but if old school techniques like stay low and do not open the nozzle until you locate the seat of the fire are employed….. any delay in getting water on the fire: be it a poor stretch, lack of manpower to move that line efficiently through, up or down stairs, or delaying suppression as the crew is searching from the attack line while advancing (multi-tasking) then firefighters will certainly sustain a rapid fire increase situation as witnessed lately in the news with many suffering thermal insult injuries. Don’t fall victim the OUR environment, understand it, and adjust your tactics so you can ultimately get the job done!
Photo 5. (below) The front door’s full length glass pane window fails due to the heat, smoke and fire gases auto-ventilating the primary door. The box immediately leans out and the rapid inrush of air flow from the new ventilation port (front door) rapidly increases the fire conditions and flame spread. Note the roof ventilation opening has become lean and touches off the by-product (soot particles, and gases of incomplete combustion). Conditions on Floors 1 and 2 get better for a few short minutes. Hence the uneducated firefighter operating in today’s fire dynamic world can quickly become a victim of the environment. Once again any delay in locating the seat of the fire by the engine company and the interior conditions will rapidly change for the worse!
In Photo 6. (below) Just three minutes (or 180 seconds) after the front door failed; the fire dynamics have changed throughout the dwelling and now “the box” is within its flammable range and we now have FIRE on Floors 1, 2 and throughout the attic area.
Photo 7. (right) This picture of Side Delta (the gable end) post flashover on all levels of the dwelling. The plate glass windows on floors 1 and 2 have failed.
Through the use of an ISG Thermal Imaging Camera, we were able to see readings of 1000 degrees F (at the floor) and 1200 degrees F (at the ceiling level)
Firefighters today must become “Educated-Aggressive” and learn as much as they can about ventilation limited and flow paths. Without knowledge about the newest indicators of predictable rapid fire increase, “Bad things will continue to happen to good firefighters” (FETC) We are not advocating the operational tactic of exterior attack on smoke, but we wanted to show that if you decide to make an aggressive interior attack, the timing of ventilation in concert with suppression has never been more critical, without delay so we can continue to operate from the inside…
We would like to thank Chief Tom Vanderbilt and all of the members of the Dublin Fire Department for allowing FETC to provide real-world training in conditions firefighters are expected to work in.