SEARCH IN THE MODERN ENVIRONMENT

SEARCH IN THE MODERN ENVIRONMENT

DOUG LEIHBACHER

The nature of the fire environment has changed a great deal over the past 25 years, and firefighters must adjust to it while at the same time strive to continue the best of firefighting tradition in a way that is compatible with the fire environment of the 1990s. Firefighters today are in many ways at greater risk than firefighters a generation ago. National death and injury surveys (by the NFPA/FEMA) show that while the overall number of firefighter deaths has been declining as the number of structure fires goes down, a higher percentage of firefighters are dying as a result of precipitant fire development phenomena such as flashover, backdraft, and rapidly spreading wind-driven flame fronts. Between 1980 and 1989, some 44 firefighters lost their lives as a result of rapid fire development phenomena, according to the most recent NFPA/FEMA study in this category. An increase in this trend will likely be seen when statistics are analyzed for the 1990s.

Each firefighter must size up the fire environment he is about to enter and initiate a search appropriate for that environment. A wrong decision could cost a life. The firefighter who initiates a search without the protection of a hoseline is at greatest risk. Important factors in the modern synthetic environment include the following:

•Building contents. Years ago, most combustible building contents were made of cellulosic materials commonly found in nature. Chairs and tables were made of wood. Sofas and bedding were made with cotton batting and jute. Carpeting was made with wool and cotton fibers, draperies with linen and other natural materials. To have a hot fire, a petroleum-based accelerant like gasoline was needed. In fact, firefighters and fire investigators used to believe that any fire that spread rapidly was out of the ordinary and indicated the use of an accelerant. Nowadays, the furnishings themselves are constructed with petrochemicals such as polyurethane foams and hard polystyrene plastic. In essence, they have the accelerant built into them. They produce quantities of heat exceeding those of ordinary combustibles. Furthermore, the smoke produced is a lot more toxic.

In addition, there are more contents than ever before. The fire load in residential structures, measured in pounds per square foot, has more than doubled in the past 50 years. Given these factors, the rapid fire expansion phenomenon known as flashover has become a more common occurrence at ordinary fires and one that all members must consider when performing search operations.

•Flashover and synthetic furnishings. The potential for flashover is exacerbated by synthetic furnishings in the modern environment. Laboratory studies have shown that flashover tends to occur within three to 10 minutes after the fire starts. The length of time, of course, can vary a great deal in the field. The amount of time it takes to reach flashover depends on many factors including room size, the composition and heat release rate of the fuel packages, ceiling height, fire load, location of contents in the room, and the oxygen supply. Smaller rooms and lower ceilings favor early flashover. Conversely, poured concrete walls and ceilings absorb heat and moderate its buildup and re-radiation. There must also be an inflow of oxygen to sustain combustion.

As mentioned, synthetic room contents, especially foams and plastics, can produce more smoke than ordinary combustibles. Smoke contains a variety of flammable gases, partially consumed carbon, and varnish-like pyrolyzed fuel particles.

In addition, the heat of combustion and the rate of heat release are also important when considering flashover. Synthetic room contents produce more heat than natural products and approach the heat levels of highly volatile flammable liquids.

Other factors that influence flashover are combustible wall coverings, such as paneling, and the location of the fire in the room. A fire starting against the wall, for instance, will grow more rapidly than one in the middle of the room.

•Thermal pane windows, insulation, and the backdraft phenomenon. During the energy crisis of the 1970s, oil prices climbed dramatically, and home heating bills soared with them. To contain energy costs, older houses were insulated and newer homes were built to meet new energy-efficiency standards designed to literally hold in the heat. Building codes in colder climates required thicker, better-insulated exterior walls. Insulation was added to attic and ceiling spaces.

In the late 1980s, energy-efficient measures included the installation of heat-conserving thermal pane windows to replace drafty, single-pane windows. With construction engineering geared toward holding in heat, it`s no wonder that the upper walls and ceilings have a diminished ability to conduct heat away from the fire room. As a result, temperatures build to higher levels than were ever previously encountered.

At the same time, many thermal pane windows are not breaking and venting heat to the outside the way the older, single-pane windows did. Many experts believe that this heat-retention ability has directly contributed to the increased frequency of flashover. Without these superheated room temperatures, fires would culminate in the growth stage without evolving temperatures great enough to trigger flashover. The melting temperature of old single-pane window glass is 1,3007F to 1,4007F. Cracking begins to occur in the 7007F to 8007F range. This breaking temperature varies with the age, thickness, and the temperature variation between the center of the window and the edge of the window protected by the sash. In the case of double-pane windows, when the inside pane breaks, the outside pane remains intact. Tests have shown that in a fire situation, cracks can occur in the inner pane in as little as five minutes. However, cracks in the outer pane do not occur for at least 13 to 20 minutes. Even when these cracks occur, the outer panes tend to maintain their integrity. Note that the heat-retention properties of thermal pane windows under fire conditions may vary with the material used to construct the frame. A vinyl frame will deform and melt at a temperature well below that of the window glass, thus creating the potential for early self-venting. However, an aluminum-constructed frame will withstand temperatures in excess of 1,200 degrees F before failing, thereby delaying the release of heat to the outside.

If fire in the late growth stage is denied sufficient oxygen, instead of building to flashover, it will begin to smolder. The heat level will be very high, and the smoke will be very thick, filling the room with flammable particles of pyrolyzed fuel and explosive gases–the elements needed for backdraft. Though less common than flashover, backdrafts are happening more frequently than ever before, especially in winter, when buildings are closed up. Energy-efficient thermal pane windows may be contributing to this phenomenon. They seal well and do not break out when exposed to heat as readily as single-pane windows. Thus, they are less subject to self-venting. This chokes off the supply of available oxygen while holding in the heat, and fires enter the smoldering stage more readily than ever before. As a result, proper size-up of the phase of the fire followed by vertical ventilation and control of all doors is crucial.

•Smoke detectors make earlier arrival possible. By the mid-1980s, smoke detectors were mandated by law in many communities and are now present in many homes and businesses throughout the United States. Similarly, alarm systems are becoming more and more common as a result of security concerns. Together, they have had a positive impact on life safety, because they alert occupants early on, before the fire develops to large proportions.

In turn, firefighters are notified earlier and often arrive on the scene while the fire is still in the growth stage, just prior to the time frame when flashover is likely to occur. Firefighters going in to perform initial search and rescue operations must take this into account. This is the time when members can be caught in a flashover.

Residential fires account for approximately 80 percent of all our fire incidents. When told that a family member is still inside, the search team will be inclined to enter immediately, without the protection of a hoseline. Firefighters who make this attempt must size up the situation carefully as they enter an unfamiliar structure during preflashover conditions, In two-thirds of the cases in which firefighters are killed searching for an occupant who was reported to be trapped, the occupant had already escaped the structure.

•SCBA and bunker gear. Self-contained breathing apparatus (SCBA) were introduced to the fire service in the 1940s and were in widespread use by the early 1970s. Prior to the advent of SCBA, searching firefighters were forced to breathe hot fire gases and caustic smoke. Under these punishing conditions, they would push in as far as they could, but often that wasn`t very far. Ironically, the thick wall of smoke presented an impenetrable barrier that often protected them from getting in too deep.

In the late 1970s, the fire retardant fabric Nomex® began to replace the canvas and rubber that previously had been used for turnout coats. Liners, which had been removable, were sewn into coats, effectively providing a layer of insulation from heat for all firefighters. By the late 1980s, hip boots were replaced with bunker pants, PASS devices were hung from SCBA, and Nomex® hoods protected the ears and neck. By the mid-1990s, firefighters were completely encapsulated by their equipment. On the plus side, many burns were prevented, and it was no longer necessary to choke on smoke. On the minus side, it was no longer possible to gauge the level of heat. Firefighters could go even deeper into the fire in search of victims.

Some firefighters make the mistake of thinking that the presence of Nomex®. or PBIT Kevlar® rendered their turnout gear fireproof–the equivalent of an asbestos entry suit. Nomex® will resist burning until it reaches 700 degrees F to 750 degrees F, and PBIT Kevlar® extends the protection to the 1,000 degrees F to 1,200 degrees F range. Experts generally agree that neither will protect you for more than a few seconds in a flashover or backdraft situation. Note: These temperatures are reduced if turnouts are contaminated with smoke particles or hydrocarbons. They must be laundered regularly.

Others make the mistake of going beyond the point of no return in search of victims who could not possibly have survived–as described by Deputy Chief Vincent Dunn (retired) of the Fire Department of New York. To be sure, this equipment has prevented many severe burns, but it cannot shield you from an engulfing flame front. It is not a proximity or an entry suit. Firefighters must adapt to this new equipment by observing the fire stage, recognizing the signs of flashover and backdraft, and adjusting their tactics to safely benefit from its use.

To summarize, the firefighters of the 1990s go deeper into fires that burn hotter, in rooms that hold heat better, using gear that shuns the smoke barrier and belies the heat level. Under these circumstances, firefighters can unwittingly contravene safe search procedures and get in too deep to get out. The only piece of equipment that can protect us is our brain. With this in mind, let us consider what we might do procedurally to make search operations safer in this modern fire environment.

SEARCH AND SIZE-UP

Search is generally separated into two categories, primary and secondary. A primary search is an immediate effort to find and remove trapped occupants. It is undertaken at extreme personal risk. It must therefore be done expeditiously and at times in an abbreviated manner, with due regard to your own personal safety. In a primary search, firefighters are attempting to beat the clock.

A secondary or follow-up search is performed after the fire has been confined. It is far more comprehensive. The search team has the opportunity as well as the obligation to be meticulous. It is important to keep in mind the difference between a secondary search and a primary search. The degree of rigor incorporated into the primary search ought to be dependent on the stage the fire is in, the probability of having a trapped victim, the stability of the structure, the progress of the other companies on the scene, the availability of water, and the danger to the personal safety of the search team. Therefore, it is imperative that the search team size up the fire conditions prior to initiating its search and continuously reassess the fire conditions while engaged. This size-up must include a determination of what phase the fire is in. Is it in the early growth (incipient) stage, the later growth stage (preflashover), the fully involved stage, or the smoldering stage? The aggressiveness of the search will vary based on this assessment.

Early Growth

A fire in the early growth stage is readily confined and extinguished. The fire is limited to the fuel “package” in the area of origin. Generally speaking, a fire in this stage presents a somewhat limited threat to firefighters and occupants, provided it is treated with due regard. Excessive heat is not yet being pumped into the upper levels of the room, and explosive fire gases are not yet being created to any great degree. Visibility is relatively good, and smoke color is usually light gray. Ambient room temperatures are still relatively low, such that firefighters can usually stand upright. The fire has not yet penetrated through the wall or ceiling surface to involve the structure. Flashover is an eventuality if nothing is done to intervene.

In such circumstances, the location of the fire in relation to the room is important in assessing the speed at which the fire will grow. A fire against a wall will grow faster than a fire in the middle of the floor. A fire in the corner of the room will spread even faster. A small fire can quickly grow to encompass an entire room and spread out from there. Do not treat an early growth fire complacently. In some cases, it takes only a few seconds. Conducting a search under these conditions will involve the removal of persons in the immediate vicinity of the fire. The fire should then be confined by closing a door to the fire room to retard fire spread while injured disabled or disoriented occupants are removed and areas more distant from the fire are checked. Note: Pay special attention to small fires in closets. Take the time to close the door before searching away from the closet. Because of the high fire loading and small area, fires in closets, under the right conditions, can extend to engulf an entire room in a matter of seconds.

Smoke can provide valuable clues about fire development. When performing a search during the early growth stage, it is imperative that all members continuously monitor the color, temperature, density, and level (distance from the floor) of the smoke. Any sudden change may indicate an immediate danger to operating personnel.

Late Growth Stage

Performing a search during the later growth stage of a fire`s development is extremely dangerous because flashover may be imminent. Fires in the late growth stage pump large amounts of superheated, explosive gases into the room`s upper areas. The heat level ranges from approximately 300 degrees F in the room`s lower portion to 1,200 degrees F or more in the upper portion. The fire is burning freely and is spreading throughout the room`s contents. Without intervention, it will likely lead to flashover, which will initiate the fully involved stage of fire development and drive temperatures up to the 1,800 degrees F to 2,000 degrees F range.

Early indicators of a possible flashover include the following:

•The heat levels require that the search team members drop to their knees and crawl.

•There is diminished visibility as the hot smoke darkens and banks down close to floor level.

•Flame, if it is visible through the smoke, will reach ceiling level.

•You can hear the fire crackling or roaring and plaster falling.

In these conditions, conduct an abbreviated primary search. While doing so, look up toward the ceiling frequently for signs of flame rollover in the smoke overhead. Also, expose the back of your gloved hand from time to time to gauge any changes in temperature. When entering an involved room, stay within five feet of the entry door. Remember that if the room flashes over, the flame front will not stop at the door; it will travel down the hallway to a vent opening that may be in your path of egress. Reach behind the door if it does not open readily. A victim may be behind it. If on a ladder at a window, reach down below the sill. Many occupants collapse just before they reach an exit.

Late indicators of flashover include the following:

•There is a rollover of flames in the smoke above your head.

•Hot, billowing smoke is surging, bulging, and pushing out of the door or window.

•The smoke, along with heat, is quickly and violently pushing down to the floor.

If you observe these indicators, get out immediately, close the door behind you, and wait for a charged hoseline because a flashover is imminent. Water is the only thing that can preclude a flashover. At this stage of development, search should be conducted only in conjunction with a charged hoseline.

The Smoldering Phase

Fires may run out of fuel or oxygen before a flashover occurs. In this case, heat levels will remain high, approaching 1,000 degrees F at ceiling level, but open flame will diminish and go out. If you encounter this stage of fire development, you must consider the possibility of a backdraft. Your size-up should include an assessment of the following:

•The presence of hot, black-stained windowpanes or the presence of thermal pane windows;

•Thick black or yellow/gray smoke pushing or puffing from the building openings;

•Smoke being drawn back into the building; and

•A high heat condition inside with no visible flame.

If these signs are present, postpone the search until vertical ventilation can be effected.

Fully Involved

If a flashover or backdraft occurs, the fire will reach its fully developed stage. Fuel and oxygen will be consumed at a very rapid rate. Flames will be blowing out of all openings, fully encompassing them. During this stage of fire, you will not be able to conduct a search in the vicinity of the fire until hoselines are in operation. Any victims still inside the room will not survive. Search at this stage involves probing the uninvolved areas remote from the fully involved room(s). Consider wind direction and velocity, since flames can be blown back into the structure toward uninvolved areas.

Wind-Driven Flame Fronts

Wildland firefighters have studied the effects of wind on forest and brush fires for many years. In recent times, the deadly effects of wind have been observed to have a tremendous impact on structural fires as well, especially those in high-rise districts. Always include wind direction and velocity in your search size-up, especially in high-rise buildings, where wind currents aloft can be much more intense than those at street level. If initiating a search without a hose stream, regardless of the fire`s stage, first check the wind conditions.

The wind`s force and direction can sometimes be checked on your way to the fire floor. When you reach the floor below the fire, go into the apartment or office below the fire occupancy, open a window, and check the wind conditions there. If the wind blows into the window with force at that point, it will do the same on the fire floor. In this case, horizontal ventilation will only increase the fire`s intensity and may cause it to spread rapidly. If the fire suddenly causes the window to self-vent, the incoming wind can create flashover-like conditions in the fire occupancy as well as in the hallway leading to it if the door has been left open.

When firefighters open the door to a burning room or apartment, one of several things can happen:

•If wind is not a factor (calm) and the room is vented on the far side of the fire, air from the door through which you enter will be drawn into the base of the fire. The fire will intensify but, in most cases, will be drawn toward the window and vent there.

•If the wind is blowing in through the window at a velocity great enough to overtake the pressures created by the fire, cross-ventilation will occur, and the fire will be drawn toward your location at the entry door.

GENERAL SEARCH GUIDELINES

•Always have a plan; never search aimlessly. If you receive a report of a trapped victim, get as specific a location as possible before entering the building. Try to ascertain the floor number and exact room in which the person was last seen. Also, verify whether the victim is a pet or a human. Distraught persons have been known to refer to their pets as “my baby.”

When a specific location is not available, search the areas where people are in the most jeopardy first–usually the fire floor; the floor above; and the top floor, where the fire is mushrooming. Decide whether you will do a left- or right-hand search. Maintain contact with a wall at all times. Whenever possible, check the layout of the apartment on the floor below the fire as you make your way to the fire floor. Look for a second means of egress. If you must search large areas or basements containing aisles of stock or if you encounter maze-like conditions, use a rope that is secured to the point of entry.

•Bring a fully charged 212-gallon water extinguisher with you if searching without a hoseline. The extinguisher can momentarily cool superheated fire gases at ceiling level and buy you time. However, you must know its limitations. It will not prevent a flashover. At best, it can delay one for a few seconds. Realize, too, that a fire knocked down in a preflashover environment can and will reignite and spread rapidly.

•Whenever possible, search off the hoseline. Many rescues has been made to the right or left of an advancing hoseline. Just as coordinating horizontal ventilation with the placement of a charged hoseline is a tried-and-true tactic, so is coordinating a search operation with a hoseline. This is the key to safe search operations in a synthetic environment. The line not only provides a deterrent to flashover, it also provides a point of orientation as well as a pathway out of the building. Incidentally, the advancing nozzle team should not hesitate to put water on hot, dense smoke if preflashover conditions are encountered. If done quickly with a straight pattern, it will not unduly upset the thermal balance or create excessive water damage.

Sometimes, aggressive forcible entry and search teams make the mistake of pushing into the fire occupancy in front of the nozzle team. When this happens, they may have their helmets knocked off by the hose stream, get steam burns, and generally obstruct engine company operations. Part of the search team`s job, of course, is to locate the fire. If, for example, the interior search team has crawled down the public hallway and found a door glowing cherry red, that team has located the fire for the engine company. If a search cannot be safely initiated, the team`s primary responsibility then becomes to control the door. Its secondary responsibility is to direct the engine company to its location. Its next job is to force the door, if necessary. When the line is charged and the nozzle is bled, open the door and let the engine company go in first and hold the fire. Give engine company members a chance to make the room or hallway, and then enter behind them and search off the line to the right or left. Do not jump in front of the line or attempt to get in before it.

When initiating a search, feel the door before you enter. The temperature of the door will usually indicate the conditions behind it. When a door is opened, it must be controlled. Don`t rush right in; stay to the side and observe the conditions: What is the smoke level? Are flames rolling out? Is air being sucked in? Is it ready to blow? Use this information to decide how you will search. If you encounter resistance when you push the door open, a victim may be on the other side. Be sure to check behind it. If a chain latch is engaged on the inside of the door, someone is likely to be inside unless he could have left by another means.

•If preflashover conditions are present, do not penetrate deeply into the room unless you suspect a victim is present. Even then, remember that if you penetrate more than five feet into the room and a flashover should occur, you may not survive. Hooking your hand or foot around the door jamb as you sweep the floor inside the room can keep you within the five-foot boundary.

•Check the wind conditions before initiating the search. How much wind is there? Which direction is it coming from? Firefighters have been killed while trying to search against the wind, from leeward toward the windward side of the fire. Wind will not only blow the fire at you, it will also supply additional oxygen, thus affording the fire an opportunity to burn faster. If you can search with the wind behind you, it can work in your favor.

•Always search in a team, not individually. In a complicated or unfamiliar layout, have one firefighter remain at the entry point. This firefighter`s job is to monitor conditions outside the room and maintain audible contact with the member searching inside. This firefighter acts as an audible tether for the member inside, who will be able to crawl toward the voice should he become disoriented.

•Be sure the incident commander knows your location at all times, and use extreme caution when going above the fire floor or past the fire before a charged hoseline is in place. The chief officer is usually the most experienced individual on the fireground. You are his eyes inside the building. It is important to advise the chief of what you`ve encountered and any changes in the heat level or smoke condition inside. He must also be advised of your progress and whether you can complete your search. At the same time, the chief is keeping an eye on the conditions outside the structure and monitoring things you can`t see. He is especially observing the pressure of the smoke pushing out of the upper levels of the structure, above your head. When the chief officer feels that it`s time to get out, it`s not open for debate.

•Size up the windows. Are the windows thermal pane? Are they blackened from smoke stains? Are they covered by security gates, child guards, or iron bars? If so, you must adjust your search accordingly. The presence of child guards and iron security gates will make it impossible for you to make a rapid escape from the windows. Your only way out will be the way you came in. Whenever window obstructions are encountered, a truck company should be immediately assigned to ladder the floor being searched and remove the bars. Even when bars are not encountered, ladder as many windows as possible.

Use caution when taking out windows if you are searching without the safety of a hoseline in the area. Under most conditions, fire will spread toward a vent opening, where it can draw oxygen. Be sure you have access to a way out or an area of refuge and are not caught between the fire and the vent opening.

•Carry a heavy tool with you whenever you conduct a search. Push it in front of you as you go, to check whether the floor in front of you is intact. The tool can also be used to extend your reach into the room. As a last resort, it can be used to breach a plaster or gypsum board wall if conditions deteriorate and to gain access to an area of refuge.

•Isolate the fire by closing a door whenever possible. This will encourage the decay stage, provide a barrier between you and the fire, and allow you to complete your search with greater safety.

•Don`t bunch up on stairways, in hallways, or in front of exits. When operating at structure fires, members have a tendency to try to get close to the fire, where the action is. Guard against this tendency. If you crowd the forcible entry, search, or nozzle team, you may unwittingly impede the team`s safe exit if it needs to get out in a hurry. In addition, members who have not been assigned a specific task or location should not be in the fire building freelancing.

•Chock the doors at your entry points so that they do not lock behind you. In a heavy smoke condition, a closed door may be mistaken for a wall and cause you to become disoriented as you attempt to exit the room you have just searched. A chock or other door-control tool will keep the door ajar and make it easier to find. It will also serve to indicate your presence to other companies arriving on the floor. Some firefighters use a flashlight to chock the door. This allows the light beam to act as a beacon, guiding you back to your point of entry.

•Create an area of refuge by forcing an apartment door near the apartment or office you are searching. One firefighter can do this quickly using a hydraram or other hydraulic entry tool.

•Whenever conducting a search, monitor the heat level as you go. Some advocate reaching up with your hand and pulling back the wristlet on the glove so that you can feel the actual heat on the back of your hand. Others recommend leaving your ears uncovered. How you do it is your business, but find some way to gauge the heat level, and do so frequently. Also, look upward as you search. Keep an eye out for signs of rollover in the smoke.

In the modern synthetic environment, fires burn hotter. Because of modern building construction techniques, the heat generated by fires is held in and not released. Consequently, backdrafts and flashovers occur more frequently than ever before. Firefighters must be mindful of this and adjust their search procedures accordingly. The issue is not about courage or toughness–it`s about physics. Proper vertical ventilation can help to decrease the hazards of a potential backdraft. Making a proper search size-up, coordinating search with an advancing hoseline, and strategically applying water into the upper levels of the room can help reduce the hazards of a potential flashover.

Traditional search procedures are tried and true. Through the years, they have effectively assisted firefighters in locating and removing savable occupants. Members assigned to search teams can minimize the inherent danger by using the procedures they`ve been taught after sizing up the existing conditions they are about to enter.

Thanks to Diana Robinson of the New York State Fire Academy; Bob Lagrow of the Rockland County (NY) Fire Training Center; and Bill Gustin of the Miami-Dade (FL) Fire Department for their assistance with this article.

Just as a search team begins to vent, enter, and search the second-floor bedrooms on the floor above, fire flashes over in the room of origin below, causing two of three windows to fail. Proper placement of the ground ladder away from the windows ensures the team`s safe egress. Once firefighters vent, the search team should size up the smoke. In this case, the moderate smoke condition indicates that the search should be initiated. However, it should be coordinated with the advancement of a hoseline on the floor below. (Photo by Paul Fialkovic.)

This fire is in the early growth stage and is beginning to heat the upper portions of the room. Virtually no smoke is being generated, and visibility is good. Since the fire is in the corner of the room, it will develop quickly.

The same fire, seconds later, is entering the late growth stage. Flames are impinging on the ceiling and upper-wall surfaces and are beginning to roll across. Smoke and fire gases are being generated in the upper portion of the room. Rollover has not yet started. (Photos by Daniel Bolline.)

Exterior shot of fire in the late growth stage. Note that rollover is occurring in the upper portion of the room. A flashover is imminent. When firefighters observe this condition and a charged hoseline is not present, they should get out immediately. (Photo by Raul Torres.)

A Fort Lauderdale firefighter prepares to enter a dwelling to search for a reported trapped occupant. Note the thick, defined smoke layer banking down and pushing out. This indicates preflashover conditions.

Seconds later, rollover occurs in the smoke layer, indicating an imminent flashover. Note the firefighter`s boot on the doorsill (arrow), as fellow firefighters come to his aid. He was able to exit safely because he correctly assessed the stage of fire and did not penetrate beyond the point of no return. The occupant reported trapped turned out not to be at home. [Photos by Mike Auteri, Dayton (KY) Fire Department.]

Bibliography

Clark, William, “Flashover, The Silent Killer,” Fire Engineering, June 1994, p. 28.

Dunn, Vincent, “Flashover,” Fire Engineering, Dec. 1990, p. 46.

Knapp, Jerry and Christian Delisio, “Flashover Survival Strategy,” Fire Engineering, Aug, 1996, p. 81.

Shields, T.J., G.W.H. Silcock, S.K.S. Hassani, “The Behavior of Double Glazing in an Enclosure Fire,” Journal of Applied Science 7:3, 1997-1998.

Doug Leihbacher, a 19-year veteran of the fire service, is captain of Engine 303 in the Yonkers (NY) Fire Department. He has a bachelor`s degree in education and is a New York state-certified fire instructor and municipal training officer.