Fire fighters in the Lakes Region have added a new term Flashover! to their vocabulary of fire fighting terms, and a new respect for this spontaneous firestorm that can take their lives. Recently the Sebago Fire Department hosted a joint training session for about 30 fire fighters from Bridgton, Baldwin, Waterford, Lovell, Sweden, and Sebago to recognize and deal with the deadly phenomenon of flashover that they may encounter while fighting structure fires in their communities.

Flashover is the most dangerous time in the life of a fire. It is the phase between the growth stage and fully developed stage of a fire. Heat is radiated from burning combustibles, like chairs, tables and draperies and is then reradiated by the walls and other structural elements. This thermal feedback raises everything in the room to ignition temperatures and the entire room and its contents ignite in a violent and explosive storm of fire with temperatures of 1,000o to 1,500o F. Anyone trapped in this flashover firestorm, whether a victim or fire fighter, will probably die. Even the fire fighters' protective turnout gear and air supply will not protect them.

The United States Fire Administration recorded 105 fire fighter deaths in 2005. According to Fire Engineering magazine, flashover is a leading cause of firefighter injuries and deaths, and approximately 10% of fire fighter deaths are a result of rapid fire development: flashovers, back drafts and wind-driven flame fronts. Flashovers are more frequent today

Forty years ago flashover was rarely experienced. Up until the 1960's, the average home contained natural products of wood, cotton and other fabrics. A fire took 8 to 10 minutes to grow from inception to the fully involved stage. However, today when the synthetics, plastics and hydrocarbons that make up much of our furniture, draperies, clothes and packaging catch fire, it may only take 2 to 3 minutes from fire inception to the peak of fire growth. Tighter house construction and windows that trap oxygen inside add to the fire growth. This accelerated rate of burn and the intensity of fires contribute to flashover conditions and are a major concern for firefighting.

Also, fire fighters are responding to structure fires more rapidly than 40 years ago, thanks to common use of home smoke detectors, radio dispatch, and more efficient apparatus. Fire trucks now arrive on the scene in minutes, often during the fire's growth stage. Fire fighters are trained to enter burning structures to aggressively attack and suppress fires when they are small and to search for victims who may be trapped inside. However, this stage of the fire can also be the worst possible time to enter a burning building. It could be just prior to flashover. Fire departments around the country are seeing flashover much more often, and fire fighters continue to die because they don't understand how to recognize and protect themselves against it.

Captain Jason Greene (2nd from right) directs fire fighters to enter the live fire simulator. Photo by David Littlefield

Fire fighter training

"We saw the need to train our fire fighters about the dangers of flashover," said Sebago Fire Department Captain Jason Greene. "There are some good, hands-on simulations available, and we arranged for them to come to Sebago to work with us. Hopefully, this training will help save a life."

Capt. Greene is the Training Officer for the Sebago Fire Department. He made arrangements for Walter Morris, a Maine Fire Training coordinator, to come to Sebago on a training drill night to give a two-hour classroom training session (lecture and video) on the science and warning signs of flashover and safe operating procedures.

"My primary goal is to teach fire fighters to recognize the warning signs of flashover and realize the limits of their protective gear," Morris said. "They used to be able to rely on their ears - nature's heat sensors - but with nomex hoods and protective headgear fire fighters must rely on other signs to warn them."

The fire fighters were told how flashover occurs, as well as the warning signs of smoke, heat, and rollover. They learned how to delay flashover to gain valuable time when there is a delay in the placement of the first attack hose-line, or for fire fighters to be able to leave a building safely. Most importantly for fire fighters' safety and survival, they learned about defensive fire fighting procedures - how to search for victims and stay alive.

Training with a Live Fire Simulator

Capt. Greene made arrangements with the Waterford Fire Department to bring their Fireblast 451 mobile live fire-training simulator to Sebago give fire fighters real life exposure to flashover conditions. The simulator is a 52 foot steel semi-trailer set up with partitions and doorways inside, and equipped with propane burners to generate intense fire that realistically simulates flashover conditions. The Fireblast 451 is manufactured in Riverside, California and is named after the title of Ray Bradbury's "Fahrenheit 451", his 1967 novel about book burning.

Fire fighters inside the live fire simulator experience the firestorm of a flashover. Photo by Allen Crabtree

Waterford purchased the Fireblast 451 simulator with a 2004 grant from the Department of Homeland Security (DHS) Assistance to Firefighter Grant (AFG) program. It is one of two simulators in the state of Maine; the other is in Gorham. The simulators are available to fire departments around the state to help train fire fighters in different aspects of structure fire attack. Greene sent out an invitation to all the neighboring towns to send their fire fighters to the training in Sebago, scheduled for the parking lot next to Station 1 in Mud City on Palm Sunday.

"We have fire fighters enter the simulator in groups of three to six with an attack fire hose," said Eric Field, Deputy Chief of the Sweden Fire Department, one of the operators of the simulator. "There they practice putting the fire out and rescue and search drills. They are able to experience first-hand what it is like to be in a structure fire under flashover conditions, and as a result are better equipped to deal with this danger if they experience it in an actual structure fire." Tony Sclafani of the New York Daily News Police Bureau described in an article that fire fighters of the Fire Department of the City of New York (FDNY) are given intensive flashover simulation training because of the real threat that flashover fires present: "It's the most realistic on-the-job training the nation's largest department has ever had. It's 11 minutes in hell."

There is a thin line between training and realism. Strict safety controls are specified for live fire training under the National Fire Protection Association (NFPA) code 1403 to help protect those being trained. Fire fighters have died during live fire training and these safety measures are intended to prevent that from occurring. NFPA's R. Fahey reported that 10 fire fighters died as a result of injuries while participating in live fire training exercises during the period 1983 to 2002.

"We have at least four safety officers stationed in and around the unit when fire fighters are inside," said Tim Cook, Sebago Fire Department Safety Officer. "The unit also has safety interlocks and an automatic shut down system with a safety officer monitoring the exercise from an insulated control booth."

Fire fighting is a dangerous business, and the volunteers who man most of the fire departments in Maine need all the edge they can get. This training to recognize and deal with flashover is crucial to doing their job efficiently and safely.

Last updated April 16, 2006

Copyright © 2006, Allen Crabtree

Published in the Portland Press Herald, Neighbors Section