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Evacuating People from Burning Buildings
By Chief Vincent Dunn
There are several strategies for evacuating
people from a burning building. 1. There is a strategy of removing people at
the same time as you fight the fire; 2. there is another strategy of removing
people and not fighting the fire; 3. and finally there is a high rise
strategy of not removing all the people and fighting the fire. This is called
a defend in place strategy. This article will examine these three strategies
for evacuating people from a burning building.
1. Evacuating people and fighting the fire strategy
During a fire, if resources are available, the chiefís strategy may be to
fight the fire and evacuate the people from the burning building at the same
time. Only a large fire department can conduct firefighting, and evacuation of
a building at the same time. Engine company firefighters stretch the hose and
extinguish the fire while ladder company firefighters may perform rescue and
evacuation. This strategy may be carried out when the burning building is a
low-rise building and there is not large number of people to be removed. The
people are removed from the proximity of the fire during the initial stages of
the fire. And if the fire is not extinguished, all the occupants may have to
be removed during the firefighting operation. The ordinary, brick and joist
construction or wood constructed building is combustible and cannot be
depended upon to stop spreading flame or smoke.
2, Evacuating people and not fighting the fire
If the fire chief of a small rural department does not have the resources he
can not evacuate people from a fire and conduct fire extinguishments
operations at the same time. To conduct rescue and firefighting you need
large number of firefighters on the scene, a good water supply and close
hydrant spacing and at least three pumpers.
In a small rural department with a single
pumper response, manned by two or three firefighters, in an area where there
is no hydrant system, when arriving at a structure fire beyond the control of
a single hose line, the strategy may have to be to evacuating people, without
firefighting. All three firefighters may rescue people until reinforcements
arrive.
3. Fighting the fire and not evacuating the building.
A high rise is generally defined as a building over 75 feet in height. During
a high rise building fire, people cannot be evacuated from the burning
building. This is because: one, there are too many people in the high
rise building; and, two, removing all the occupants of a high rise
building could take several hours; So the strategy of a fire chief at a
burning high rise building must be ědefend in place strategy. This, ědefend in
place strategy , means firefighters fight the fire without evacuating all the
people. In a high rise office building the fire service uses a partial defend
in place strategy. In a high rise residence building the fire service used a
total defend in place strategy.
Evacuating people from high rise office buildings
During a high-rise office building blaze we
must fight the fire while most of the people remain inside the burning
building. The fire chief orders the people on the fire floor and the floor
above to leave and instructs all other people to remain in the building unless
smoke is building up on there floor. They should notify the chief if smoke is
seeping onto the floor and that floor will be ordered evacuated by
firefighters. In order to use a defend- in ‚place firefighting strategy the
building must be fire resistive construction, have automatic sprinklers and be
compartmented with wall and floors to resist smoke spread. Floors and rooms
inside a fire resistive building must become areas of refuge free of flame and
smoke. in order for people to remain during a fire. Since the collapse of the
world trade center towers, the defend in place strategy is questionable. The
strategy of high-rise firefighting depends on three factors. One, The
building is fire resistive-smoke and fire will be confined to one floor;
Two, the fire is of a size that can be extinguished by firefighters less
than 2500 square feet; and Three, the people in the building will
comply with the instructions of the fire chief. In my opinion none of the
above are true today. Todayís high rise buildings with central air system are
not fire and smoke resistive, firefighters can not extinguish fires in large
area office floors-10 and 20 thousand square feet and finally, people will not
comply with the chiefs instructions after the world trade center fire and
collapse.
Evacuating people from high-rise residence buildings
During a high rise residential building blaze we must fight the fire while all people in the building remain in the burning building. The strategy for evacuating people from a high-rise residence building is different than the strategy of evacuating people from a high-rise office building. A high rise residence building, like a commercial building, is defined as a building over 75 feet; and a high rise residence is required to be fire resistive construction. In a residence building the apartment walls and floors can resist the spread of flame and smoke. In a high-rise residence building there is no open floor design. Each floor in a residence building is subdivided into apartments. If the door to the apartment is closed after the person leaves the burning apartment, flame and smoke will be confined to the apartment of fire origin and can not spread throughout the floor. So, during a fire in a high-rise residence, the fire chief orders all people to remain inside their apartments while the fire is extinguished. People are not ordered to leave the fire floor nor the floor above the fire. This is a ěTotal- defend- in -place- strategyî. It is unlike the ě partial, defend- in -place strategyî used in a high-rise office buildings.
Area of refuge-Evacuating people
horizontally
When you remove people from the danger
of a spreading fire in a burning building you usually take them down a
stairway, or down fire department ladders, below the fire. If a person is old,
injured or disabled taking them usually one or two floors below a fire and
leaving them there they will be safe. Note: this was not the case at the world
trade center on 9-11-01, which had floors, constructed of lightweight bar
joists. Fire, heat and smoke rise upward, so people are taken down a stair or
ladder below the fire, heat and smoke. However, there are some times when you
do not take them down below the fire, but instead move people in a horizontal
direction away from the fire, behind a fire resistive barrier into an ěarea
of refugeî. This is horizontal people evacuation. This is the evacuation
strategy used in high-rise buildings such as, hospitals, schools, places of
public assembly and prisons that are constructed into separate structures.
These buildings are constructed into fire resistive sections. Fire resistive
walls and doors which can stop flame and smoke subdivide each section of the
building. When a fire occurs in one section people are taken from that section
into another, and fire resistive door closed to the section where the fire is
burning to restrict its spread. Once in the safe area of refuge the people may
or may not be taken down the stairs to the street.
Method of evacuating people from fire danger
There are priorities on how firefighters
should assist people from a burning building. People should always be removed
from a burning building using the safest possible way. A firefighter can
increase the victimís risk of death and injury by the way the person is
removed from the fire. Fire photos sometimes show firefighters erroneously
taking a person from a safe location, at a window or fire escape on the floor
below the fire, onto a shaky aerial ladder 50 feet above ground
There is a priority of how people should be rescued from a burning building based on safety of the victim being removed. The method of removing people from a fire in priority of safety is: use the smoke proof tower first. If not available, use an enclosed stairway or next, a fire escape. Using an aerial platform is safer than taking a person down an aerial ladder; the last resort is a rope rescue.
Bio:
DEPUTY CHIEF VINCENT DUNN (retired) was a veteran of 42 years on the Fire Department of New York (FDNY), formerly of Engine 59, Engine 33, Engine 58, Battalion 25, Division 7 and retired from Division 3. He is the author of Safety and Survival on the Fireground and Collapse of Burning Buildings. Fire Engineering Books recently released his newest book, Command and Control of Fires and Emergencies. He developed and taught a number of courses for the FDNY, the FBI and the National Fire Academy and is a regular contributor to WNYF. He has a masters degree in urban studies, a bachelor’s degree in sociology and an associate degree in fire administration from Queens College, City University of New York.