Wilmington, DE -- July 21, 2004 -- Flashover! Even though firefighters are beginning to understand it, this fatal phenomenon is still shrouded in a veil of mystery. Experts in the fire training arena have differing opinions and descriptions of Flashover, but they all seem to agree on one thing. It's a nasty thing!
Simply put, room and contents begin to burn at a very rapid rate during the growth stage of the blaze. Heat is radiated from burning combustibles, like chairs, tables and draperies -then reradiated by the walls and other structural elements. This "thermal feedback" causes an even greater acceleration of heat. Finally, the entire room, and its contents, ignite with violent and explosive force.
Our culture and its technology have served as a major contributor to the problem of flashover. Up until the 1960's, the average residence contained natural products made up of woods, cottons and other fabrics. Back then it often took a blaze from 8 to 10 minutes to grow from inception to the fully-involved stage.
But in our present day world of synthetics, plastics and hydrocarbons, the same room takes only 2 to 3 minutes to reach the peak of fire growth. This accelerated rate of burn has become a major concern for firefighting teams and the officers who command them.
Oddly enough, it was a prevention tool designed to save lives that first brought Flashover to our attention - the home smoke detector. In days gone by, fires were typically unreported until they vented from a window, sending the fastest civilian running for the Gamewell Box. Today, because of the effectiveness of early warning systems, departments are now notified of fires much, much earlier.
Companies now arrive on the scene during the growth stage, entering the structure at the worst possible time, just prior to flashover. Combine this with the standing practice of aggressive interior attack, and one can quickly understand why firefighters have become more aware, and much more concerned, of the phenomenon. The simple fact is - we're seeing it much more often.
-Low Tech System with High Tech Results-
In Europe, where line of duty deaths, and interior attack, are quite rare, the fire community as a whole was shocked when, in 1987, two Swedish firefighters lost their lives to a flashover incident. In response, training officers in Stockholm saw the need to create an awareness program for its firefighters. They developed a rudimentary simulator that allows attack teams to identify potentially dangerous environments during the early stages of the firefight. Their primary goal: to demonstrate to suppression teams how to escape a flashover, and exit safely!
On the fire training grounds near Stockholm, I prepare to videotape the special simulator designed by the Swedes. I was expecting a high-tech block structure, with thermal sensors, gas jets, and emergency sprinklers. Instead, I'm led to a series of Overseas shipping containers, that have been laid out in random fashion to represent various firefighting scenarios.
According to Roland Lindqvist, Director of the Raddnings Verket, (The Swedish Fire Rescue Services Board) the system was adopted by all departments in Sweden in 1988. Instructors there further refined both classroom and hands-on curriculum, and today every Swedish firefighter is required to take this special training course. It's dubbed the Swede Survival System, and it's taken Europe, and this nation, by storm.
6,000 miles away from Stockholm, in America's heartland, Indianapolis firefighters carry on a tradition that's been passed down from generation to generation -- mounting an aggressive interior attack. Like so many departments nationwide, Indy fire administration have armed all front-line personnel with the very best in protective equipment. A secure envelope, that guards firefighters from intense heat and vicious flames.
But some say that this very same envelope denies firefighters the use of an important God-given safety regulator - the sense of feel. In short, present day protective gear is so damned good, it's difficult to determine when to bail out.
A 3-alarm blaze in Indy's downtown section, found three firefighters deep inside the bowels of the beast. A huge structure, the Athletic Club blaze was stubborn, and difficult to ventilate. According to other interior personnel, the trio entered a smoky room in search of the seat of the fire, but within moments the room erupted in an explosion of flame, instantly snuffing out their lives.
IFD was determined to prevent similar horrible accidents from ever happening again. They imported the Swede Survival System, and since its installation, EVERY IFD firefighter and officer has received extensive flashover training. Many, more than once.
In other departments throughout the USA, training officers have adapted the system to meet the needs of America's aggressive firefighters. Their goal, to show an uncontrolled blaze in a SAFE, controlled atmosphere. And to date, nearly fifty departments and agencies have answered the call.
-The Big Burn-
Rockland County, NY, just North of New York City. It's 0530 on a chilled Winter's morning, and although I've worked in the simulator three dozen times, this demonstration is very special. Instead of six students, I'll have a few million inside with me. A burn that will go "LIVE" to three million homes, thanks to the Fox network and their morning show, "Fox After Breakfast".
As local volunteers arrive in their rigs, Rockland County training personnel ready the simulator for this first-ever LIVE TV training burn. It's like opening the pyramids, only with much better results.
Technicians install special Ear Mics that allow me to speak to and listen to the program hosts in New York. I'll be taking a Fox reporter, a guy they call "The Road Warrior", inside the fire to explain how the system works, and why it is beneficial to firefighters. A squirrly production assistant buzzes around, refilling our coffee cups every 5 minutes or so. I'm wired in more ways than one.
It's 6:30am, and we're scheduled to go live in just a few minutes. Gerry Knapp, the Rockland commander, and a Swede instructor, signals the ignition team to light the combustibles in the "burn container", a chamber that sits 5 feet above the "classroom container" of the two level system. Using 1401 guidelines, they ignite two drums filled with wood and paper products -- no accelerants. The Swede System is no propane box, it's a true-to-life, hotter than Hell fire, that burns like the real thing. In a matter of minutes, smoke begins to bank down in layers -- then we're live via satellite.
-Hi Mom-
A firefighter/cameraman huddles with us, then cues me to begin speaking. The fire is advancing to the free burning stage, and smoke begins stratifying closer and closer to the floor. I draw the reporter's attention to the "snakes" of flame that begin to appear in the cloud of smoke. Using fire-speak terms I say, "Right now the temperature at the ceiling is 1100 degrees (F), and as you can see, convection currents are becoming readily apparent." Through my ear piece I hear the "wows" of the staff and studio crew in New York.
The reporter next to me asks, "OK Lou, when will they put the fire out?" I answer, "They won't, at least not yet." I explain to Mr. Warrior that the system allows firefighters to study fire behavior, to look at the beast, how it moves and how it exists. They'll learn to extinguish the blaze some other time, in another place. "Right now, their job is to co-exist with the fire." The ceiling flashes, and the nozzleman delivers a series of short fog bursts to cool the ceiling gases. The fire quickly dies down.
These short bursts of H2O from a Swedish made nozzle, are the real secret to training inside the Swede system. According to the Swedes and the Americans who've studied under them, delivering a low flow fog stream to the ceiling, cools the super-heated gases long enough to make a viable escape from a potentially fatal situation. Now you know why Truckies in New York, Chicago and San Francisco carry those two and 1/2 gallon "cans".
"This is New York, Lou" comes the voice in my other ear. It's Jerry Liddell, the studio producer on a secure circuit. "We're staying with you in Rockland...more flames, more flames." Damn, it's hot.
As the cameraman pans up to the ceiling, I draw attention to a special spring- loaded portal device that I operate from the floor. It allows me to vent the room of excess gases, giving the fire another chance to build. It's similar to portals that are installed in most Swedish structures, a smart-tool that allows firefighters to perform vertical ventilation in a split second, by simply pulling a chain next to the front door. "This portal permits me to generate up to seven flashover episodes during a typical 20 minute evolution.", I say.
Those of you who've studied in the Swede simulator, know what I mean when I say, it's hot! Most students are instructed to remove their helmet face shields, and it's not unusual for reflective striping to blister and burn. Nothing proves my point better than the reporter next to me.
For just a few moments, he turns his back to the blaze above our heads to address the camera. As he comments on the "feel of the room", I glance over to see that the shoulder of his new turnout coat is flaming. I make an attempt to snuff out the flames with my gloved hand, but no luck. Finally, on LIVE television, the safety team intervenes, pulling the reporter to the safety of the outside.
I follow on my stomach, crawling toward the lens of the outside camera. Not my best angle, but the image makes its point. In the background, a hose team wets down the reporter with an inch and 3/4 line. "Great job guys" says the intercom. "We'll do it for the West Coast in another hour." (???)
I should note that the Swede Survival System is much more than a container, it's an entire training package. The curriculum begins in the classroom with 8 hours of instruction, then ends in the simulator itself. If you have the opportunity to train in it, by all means do so. It's an ideal way to teach younger firefighters, and veterans, how to identify flashover through the sense of sight. After all, our vision is the only function that manufacturers and government haven't covered. Pass the thermal imager, please.
Disclaimer: All information on this site is provided for informational purposes only! By no means is any
information presented herein intended to substitute for the advice provided to you by any health care or other professional
or organization.
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