HIGH-RISE FIREFIGHTING STRATEGIES

HIGH-RISE FIREFIGHTING STRATEGIES

BY VINCENT DUNN

There are five attack strategies used at a high-rise fire: a direct frontal attack, a flanking attack, a defensive operation, a nonattack, and an outside attack.

FRONTAL ATTACK

A direct head-on frontal attack the first, most often used, and most successful attack strategy at a high rise fire. Firefighters drag a hoseline straight ahead into the path of a fire. They come face to face with the fire and extinguish it. Ninety-five percent of fires are extinguished with this strategy.

FLANKING ATTACK

A flanking attack, the second most often used strategy at a high-rise fire, often is successful when the frontal attack fails. A hose team advances toward a fire from the side. When air movements from the window or the stack effect cause flames and heat to blow directly into the path of firefighters advancing the first hoseline, it can stop their forward movement and the fire will continue to burn. A second hoseline can be stretched from the same or another stairway so the fire can be attacked from one of its sides and approach can be made from a right angle or a side. A flank attack can be launched while the first attack hoseline continues to operate. Good communication and coordination are needed so that firefighters will not be injured by opposing hose streams.

Doors are opened during the initial frontal attack, the flames may already have broken windows. The outside wind blowing into the flaming windows coupled with the air movements effected by the attack can cause a terrific wind tunnel effect of fire, heat, and smoke that can force firefighters back into the stairway and also stop the fire extinguishment. Once this wind tunnel effect is established at a high-rise fire, fire and heat blowing from the outside, down a hallway, into the core area or stairway it does not often change direction. However, this danger must be a concern when opening different doors to start a second hoseline as a flanking attack. Firefighters must be ready to retreat if the wind tunnel effect changes and blows in their direction.

At many fires, a flanking attack becomes an option when a firefighter searching for victims opens a door or moves down a hall and discovers a second approach to the fire that is relatively free of smoke and heat. If the initial hose team cannot extinguish the fire, this second flanking approach should be tried. A flanking attack often can be used at a high-rise office building because of the open floor design. A floor occupied by one tenant usually has corridors that create a circular path throughout the entire floor. Every spot on the floor can be reached from two directions. There are no partitions as are found in multiple dwellings, which have dividing partition between apartments. A flank attack rarely is used in a multiple-dwelling fire unless walls are breached.

I remember a high-rise fire at which a flank attack saved the night. It was a third-alarm fire in an office building. I was at the lobby command post for some time. The Chief of Department arrived and assumed command. I briefed him on the positions of the sector chiefs and companies. A radio report from the operations chief directing the fire attack upstairs: “We can`t move the line. Wind blowing against us. Still no progress.”

After sending arriving companies up to the staging floor for reinforcements, another report came to us from operations: “Still no progress. I am considering closing the door to the fire. Looking for another approach. Heavy fire and heat”

After transmitting another alarm for additional troops, the chief turned to me and asked, a bit concerned, “What do we do now?”

The only response I could think of was, “We have the sector chiefs in position; all companies are at their assignments. It`s up to the building to hold it now.”

Just then, the radio blared again. “Urgent! Urgent! We have found another approach to the fire. Stretching a second line. I think we can get it.”

After the fire had been extinguished, the postfire analysis revealed that the second hoseline was stretched up close to the fire behind a partition a door opened, and the fire was extinguished. The lesson learned at this high-rise fire is, when the first hose team cannot extinguish the fire, don`t stretch a second line side by side the first one. Instead, look for an alternate approach. A flanking attack may be the solution.

A pincer attack strategy is a double flanking hose attack. The first and second companies become simultaneous flanking hose teams, converging on the fire from both sides.

DEFENSIVE ATTACK

When the fire in the high rise is above the reach of an outside master stream and a frontal and a flanking attack strategy fail, the third option is a defensive strategy–sometimes called a “controlled burning” operation–in which one or two hose streams operate from a stairway enclosure while the entire contents of the floor burns out.

The fire department controls the stairways while all the combustibles on the floor are consumed. This burnout usually takes one or two hours, depending on how much combustible material is on the floor. At a defensive operation, whether the fire extends to the floors above depends greatly on the type of fire resistive construction used in the building, not the fire extinguishment strategy.

Many departments have portable deluge nozzles mounted on a wheeled platform that fit inside an elevator. During a defensive high-rise strategy, the deluge nozzle is positioned in the stairway. It takes the place of firefighters holding nozzles. One firefighter can monitor the deluge nozzle. The handlines already connected to the standpipe are shut down and the nozzles are removed. The hose supplies the defensive deluge nozzle.

Deluge nozzles have several advantages.

A more powerful stream can knock down partitions and hit the fire.

The reach of the deluge nozzle is greater than that of handheld nozzles. The number of firefighters at the stairway opening taking punishment from heat, smoke, and fire is reduced.

When a deluge nozzle is used, the pressure at the siamese must be increased. Instead of 150 pounds per square inch and five pounds per square inch for every floor above ground level, use 200 pounds per square inch and five pounds per square inch per floor. If more pressure is needed, communications from the fire floor to the pump operator should obtain it.

At a defensive firefighting operation, we are conceding the building to the fire. Flames are beyond the control of the fire department`s handheld hoselines. Controlling the fire now depends on the structure`s firestopping. If the pokethrough holes and concealed spaces are sealed with firestopping, the fire may not spread to the floor above through utility closets, air-conditioning ducts, and openings at the outer end of the floor slab.

If firefighters at a defensive operation control the stairs, a hoseline may be taken to the floor above and water flowed on top of the floor to keep it from cracking and opening. This operation, called “flowing the floor,” also may allow water to extinguish small pockets of flame coming up through openings in the floor while small amounts of water flow down through floor openings. Admittedly, this is a last-ditch effort to prevent fire spread.

NONATTACK STRATEGY

A nonattack strategy is used by firefighters at a stairway in a high-rise building when there is a serious fire on the occupancy side of a stairway door and the following conditions prevail:

Blistered paint and glowing metal are present.

A quick glance inside reveals that the fire cannot be controlled by one handline.

At the time of size-up, hundreds of people are coming down the stairs, evacuating the floors above. If the door is opened to advance the attack hoseline, the smoke and heat flowing out over the heads of firefighters would sweep up the stairs and trap the people coming down.

At this instant, there should be no fire attack. The officer in command should be notified of these conditions and this decision. A search team may attempt a primary search of the floor, but the door to the stairway must be kept closed after firefighters enter the floor. If possible, another stairway should be used to attack the fire, or a hoseline attack may be started and the door opened after all people above the fire have left and the stairway above has been cleared.

OUTSIDE ATTACK

There is a saying among firefighters: “In New York City, God looks after drunks and people who work in high-rise buildings.” Over the past 10 years, every serious high-rise fire in the city has occurred after normal work hours, when the building was empty or on a lower floor, within the reach of an outside aerial master stream, if the fire occurred during normal work hours.

At a response to a high-rise fire, the drivers of the first and second ladder companies must position their apparatus for a possible rescue or outside aerial-stream attack. The hard copy of the alarm notification gives the floor of the reported fire. The firefighter driving the aerial ladder must be given this information. If the fire floor is on the 16th floor or below and the interior frontal attack and the flanking attack fail, the officer in command may order an outside aerial stream into operation.

Firefighters operating aerial ladders should not wait for this strategy change before positioning the ladder for use. The ladder should always be positioned for possible victim removal first and outside aerial stream attack second. At some fires, the placement is the same for both.

I learned the importance of proper aerial ladder placement when I was a new battalion chief in a district that had a lot of vacant buildings. At almost every working fire as I was directing interior lines into position during the initial stages of the attack, a veteran ladder company chauffeur would come to the command post and say, “Chief, the bucket is in position. I have a dry supply line stretched. Let me know if you want to use it.”

I rarely used the aerial stream, but knowing it was available gave me the option. Most of all, it gave me the confidence to stay with an interior frontal attack strategy. In addition, when the deputy chief arrived on the scene at a fire where my frontal-attack strategy was not going so well, he did not have to start moving apparatus to switch strategy. The firefighters who already positioned the tower ladder for use made me look proactive and made the deputy`s operation effective.

After the ladder is placed for an outside attack, it should be raised to 32 degrees, the angle that provides the greatest horizontal reach. At a 32-degree angle, an outside stream has greatest penetration and reaches its objective, the fire, with the greatest force. To get the stream operating at a 32-degree angle may require placing the tip of the ladder close to the building. For upper floors, the ladder tip may have to be away from the building. An aerial stream operated at a 25- or 60-degree angle is still effective and can extinguish a fire on a high-rise upper floor.

Many fires are in outer rooms or offices that cannot be reached with interior handlines. An outside stream can extinguish a fire near the outer perimeter of a high-rise building when operated at angles of 45 to 60 degrees from horizontal.

The maximum vertical reach of an aerial stream is obtained when the nozzle is at 60 to 75 degrees from the horizontal. An aerial master stream operated at a 75-degree angle can stop flames spreading from window to window. When the stream is directed at the spandrel wall of a high-rise building (the exterior wall between the top of one window and the bottom of the window above), flames lapping out a window can be cooled and fire extension from autoexposure stopped or slowed. A properly placed 75-foot aerial ladder with a stream reach of 100 feet can reach the 16th floor, and a 100-foot aerial ladder with a stream reach of 100 feet can reach the 19th or 20th floor of a high-rise building and possibly prevent fire spread from window to window.

LESSONS LEARNED

Firefighting strategy in high-rise building fires is different from that for low-rise building fires. For example, the flanking attack is effective only in the large, open floor design of a high rise. The control-burning strategy while firefighters remain inside the building is unique to a high-rise fire. At a low-rise building fire, firefighters may withdraw outside and use master streams. Firefighters can`t withdraw to the outside at a high-rise fire. A nonattack strategy at a high-rise office building containing thousands of people could not be used at a low-rise fire. Finally, the outside aerial attack has limitations when the fire in a high-rise building is above the 20th floor.n

n VINCENT DUNN, a 38-year veteran of the City of New York (NY) Fire Department, is a deputy chief and previously served as division commander for midtown Manhattan. He developed the National Fire Academy “Command and Control of Fire Department Major Operation” course and wrote the collapse rescue procedure used by New York City fire rescue companies. He is a lecturer; is the author of the text and video series Collapse of Burning Buildings and the text Safety and Survival on the Fireground, published by Fire Engineering Books and Videos; and has had numerous articles related to firefighter safety published in fire service magazines. He has a master`s degree in urban studies, a bachelor`s degree in sociology, and an associate`s degree in fire administration from Queens College, City University of New York. He is a member of the New York City Fire Chiefs Association, the NFPA, and the IAFF. He can be reached at (800) 231-3388.

No posts to display