Friday, March 9, 2018

Essentials? Rewriting the book of firefighting over the years.

Essentials of Fire Fighting, First Edition (IFSTA, 1977)
Chapter 6 Fire Streams, Pages 174-176
Requirements For Extinguishing Structural Fires
Building fires may be divided into fires which are primarily confined within the walls, roof, and floor of a structure or building, and fires within a building which have ventilated
themselves to the extent that they are free burning into the open. Each of these conditions presents a different problem and fire fighting situation.
When fire is confined within the walls, ceiling, and/or roof of a room or building, the intense heat, smoke, and fire gases will also be confined in the burning space. The confined
building fire presents a situation that requires careful consideration to prevent further damage and to effect extinguishment. This type of fire may be considered in three different
phases for the purpose of deterring requirements. First, the Incipient or Beginning Phase; Second, the Free-Burning Phase; and Third, the Smoldering Phase. The major
difference between the three phases is from the standpoint of ventilation practices. Knowledge of these phases is also useful from a fire extinguishment point of view.
A fire in the incipient phase usually requires a direct application of water at the base of the fire to reduce the temperature of the fuel below ignition point. The amount of heat being
generated will increase as the fire progresses. Although the flame temperature will be well over 1,000 degrees Fahrenheit, the room temperature may only be slightly increased.
The major consideration is reaching the fire.
In the second phase or free-burning phase, the area will be extremely hot. A confined building fire in the second phase required a reduction of atmospheric temperature to livable
conditions so that firefighters may enter and extinguish any remaining fires by direct application but protective breathing equipment will be required for the safety of those
entering.
In the third or smoldering phase, the heated area will be filled with hot smoke and fire gases. So far as the fire gases and smoke are concerned, firefighters could enter with
protective breathing equipment, but the heat would be unbearable. Experiments and tests have shown that a building containing a third phase fire may be made tenable by
applying water fog into the most highly heated upper levels. The heat will convert the finely divided particles of water into steam thereby reducing the temperature in the space.
The expansion of steam will further force smoke and gases from the space. In this phase, the heat must be reduced, and the smoke and gases must be displaced before fresh air
can be admitted.
An open or non confined building fire is one which has burned to the outside, releasing the heated smoke and gases. The entire building may be involved and these open fires
require long-range operations. The intense radiated heat from an open fire makes it difficult to apply water directly at the base of the fire. A large volume of water is usually
required to control and extinguish this type fire, which may require straight streams and long-range fog streams. This type of fire also requires careful consideration of exposures,
with equal consideration for fire streams to protect them
A Confined Strutural Fire
The conditions that may be found in a confined structural fire and the phases of its development have again been outlined by the Analysis Table, from which we may list the
important factors of applying fog streams. Some of these important factors are as follows:
• The fog stream should be projected into the hottest space, which may be the upper levels if the fire has burned for a considerable duration.
• If a short-reach, wide-angle fog pattern will cover the area, it should be projected upward into the heated area and worked into a circular motion for complete coverage.
• If the area is so large that it cannot be reached by the short-reach, wide-angle fog pattern, a long-reach fog pattern should be used to carry the droplets into the hottest space
and the nozzle worked back and forth for complete coverage.
• The number of fog streams to use should be determined by the cubic foot area involved and the volume of the nozzles.
• Enough water fog must be applied to absorb the heat faster than it is being generated.
• One or more extra lines should be supplied for auxiliary use. They may be used to extinguish remaining fire.
• The officer in charge should watch for displacement indications: first, smoke; second, smoke and condensed steam; and third, condensed steam.
• A fog stream should but shut off as soon as smoke and gas have been displaced by condensed steam.
• If the atmosphere is still too hot, a second burst of water fog may be required.
• All spot fires may be extinguished by direct application.
• When the application of water fog is made through an opening into a building, the firefighters should keep well out of line with the opening to protect themselves from the
expulsion of heated gases and steam back through the opening.
Essentials of Fire Fighting, Second Edition (IFSTA, 1983)
Chapter 14 Fire Suppression Techniques, Pages 340-341
(RED INDICATES CHANGES FROM FIRST EDITION)


Direct Attack
The most efficient use of water on freeburning fires is made by a direct attack from a close position with a solid stream or penetrating fog pattern (30 degree or less) on the base
of the fire. The water should be applied directly on the burning fuels in short bursts until the fire “darkens down”. Streams should not be applied for too long a time or the thermal
balance will be upset. Thermal balance is the movement of heated gases toward the ceiling and after the application of fire streams that includes the spread of expanding steam
to all areas of the confined space. If water streams are applied for an excessive length of time, the steam begins to condense causing the smoke to drop rapidly to the floor and
move sluggishly thereafter.
Indirect Attack
When firefighters are unable to enter the structure due to intense conditions in confined locations, an indirect attack can be made (Figure 14.2). This attack is not desirable where
victims may yet be trapped or where the spread of fire to uninvolved areas cannot be contained. The nozzle flow setting will range from a penetrating fog (30 degree) to moderate
angle fog (60 degree) and should be directed at the ceiling and played back and forth in the super heated gases at the ceiling level. Directing the stream into the superheated
atmosphere near the ceiling results in the production of large quantities of steam. One cubic foot of water (7.4 gallons) completely vaporized will create 1700 cubic feet of steam.
Once again, the stream should be shut down before disturbing the thermal balance. Once the fire has been darkened down the hose line can be advanced to extinguish any
remaining hot spots with a direct attack.
Combination Attack
The combination method utilizes the steam generating technique of ceiling level attack with an attack on materials burning near the floor level. The nozzle may be moved in a, “T,
Z, or O” pattern starting with a penetrating fog directed into the heated gases at the ceiling level and then dropped down to attack the combustibles burning near the floor level.
The “O” pattern of the combination attack is probably the most familiar and abused method of attack. When performing the “O” pattern the stream should be directed at the ceiling
and rotated clockwise with the stream edge reaching the ceiling , wall, floor, and opposite wall. Keep in mind that applying water to smoke does not extinguish the fire and only
causes unnecessary water damage and disturbance of the thermal balance.
Essentials of Fire Fighting, Third Edition (IFSTA, 1992)
Chapter 12 Fire Control, Pages 404-406
(RED INDICATES CHANGES FROM SECOND EDITION)


Direct Attack
The most efficient use of water on freeburning fires is made by a direct attack from a close position with a solid stream or
penetrating fog pattern (30 degree or less) on the base of the fire straight stream. The water should be applied in short bursts
directly on the burning fuels in short bursts until the fire “darkens down” (Figure 12.10). Streams Water should not be applied for
too long a time or the thermal balance layering (movement of heated gases toward the ceiling) will be upset. Thermal balance is
the movement of heated gases toward the ceiling and after the application of fire streams that includes the spread of expanding
steam to all areas of the confined space. If water streams are is applied for an excessive length of time, the steam begins to
condense causing the smoke to drop rapidly to the floor and move sluggishly thereafter.
Indirect Attack
When firefighters are unable to enter the structure or fire area due to intense fire conditions in confined locations, an indirect
attack can be made (Figure 12.11). This attack is not desirable where victims may yet be trapped or where the spread of fire to
uninvolved areas cannot be contained. The fire stream, which could be a solid , straight, or narrow fog pattern, The nozzle flow
setting will range from a penetrating fog (30 degree) to moderate angle fog (60 degree) and should be directed at the ceiling and
played back and forth in the super heated gases at the ceiling level. Directing the stream into the superheated atmosphere near
the ceiling results in the production of large quantities of steam. One cubic foot of water (7.4 gallons) completely vaporized will
create 1,700 cubic feet of steam. Once again, the stream should be shut down before disturbing it disturbs the thermal balance
layering. Once the fire has been darkened down, and the space has been ventilated, the hoseline can be advanced to extinguish
any remaining hot spots with a direct attack.
Combination Attack
The combination method utilizes uses the steam-generating technique of ceiling level attack combined with an attack on
materials burning near the floor level (Figure 12.12). The nozzle may be moved in a, “T, Z, or O” pattern starting with a solid,
straight, or penetrating fog directed into the heated gases at the ceiling level and then dropped down to attack the combustibles
burning near the floor level. The “O” pattern of the combination attack is probably the most familiar and abused method of attack.
When performing the “O” pattern, the stream should be directed at the ceiling and rotated clockwise with the stream edge
reaching the ceiling , wall, floor, and opposite wall. Firefighters should keep in mind that applying water to smoke does not
extinguish the fire and only causes unnecessary water damage and disturbance of the thermal balance layering.
Essentials of Fire Fighting, Fifth Edition (IFSTA, 2008)
Chapter 15 Fire Control, Pages 767-769
(RED INDICATES CHANGES FROM FOURTH EDITION)


Gas Cooling
Gas cooling is not a fire extinguishment method but simply a way of reducing the hazard
presented by the hot gas layer. This technique is effective when faced with a shielded fire;
that is, one you cannot see from the doorway because objects are shielding it. In these
situations, you cannot apply water directly onto the burning material without entering the
room and working under the hot gas layer.
The hot gas layer accumulating in the upper levels of the compartment can present a
number of problems for you and other members of the hose team. Remember that smoke
is fuel, and it may transition to rollover, flashover or a smoke explosion at any time. In
addition, hot smoke radiates heat to furniture and other combustibles in the compartment.
This increases pyrolysis which adds more flammable fuel to the gas layer. Cooling the hot
gas layer mitigates these hazards by slowing the transfer of heat to other combustibles
and reducing the chances of the overhead gases igniting.
You can cool the hot gas layer by applying short pulses of water for into it. With the nozzle
set on a 40- to 60- degree fog pattern, direct it upward toward the gas layer and quickly
open and close it in one- to two second pulses (Figure 15.11). Remember that your intent
is to cool the gases, not to produce a large volume of steam. When water droplets begin
to fall out of the overhead smoke layer, it means that the gases have been cooled and
you can stop spraying water into the smoke. If the fire continues to burn unchecked, the
gas layer will regain its heat and the gas-cooling technique may have to be repeated.
The gas-cooling technique should be repeated as necessary while the hose team
advances under the gas layer toward the fire. In narrow hallways, the fog pattern may
need to be restricted. In large-volume compartments, the duration of the pulses may need
to be increased slightly.
Direct Attack
The most efficient use of water on free-burning fires is made by a direct attack on the
base of the fire - usually from with a solid stream or straight stream. The water should be
is applied in short bursts directly onto the burning fuels (often called “penciling”) until the
fire “darkens down” (Figure 15.12). Another effective technique (often called “painting”) is
to cool hot surfaces to slow or stop the pyrolysis process by gently applying water and
allowing it to run over the hot material. Water should not be applied for too long a time
otherwise thermal layering will be upset long enough to upset the thermal layering
(sometimes called thermal balance); the steam produced will begin to condense, causing
the smoke to drop rapidly to the floor and move sluggishly thereafter.
Essentials of Fire Fighting, Fifth Edition (IFSTA, 2008)
Chapter 15 Fire Control, Pages 767-769
(RED INDICATES CHANGES FROM FOURTH EDITION)
2008


Indirect Attack
When firefighters are unable to enter the structure or fire area due to a burning building or compartment because
of the intense fire conditions heat inside, an indirect attack can be made from outside the area compartment
through a doorway or window or other small opening (Figure 15.13). This method of attack is not desirable ideal
where victims building occupants may yet be trapped still be inside or where the spread of fire to uninvolved
areas cannot be contained. However, this may be the only method of attack possible until temperatures are
reduced. The fire stream, which could be a solid , straight, or narrow fog pattern, should be directed at the
ceiling and played back and forth in the superheated gases at the ceiling level.
To make an indirect attack on the fire, a fog stream is introduced through a small opening and directed at the
ceiling where the heat is the most intense. Directing the stream into the superheated atmosphere near the ceiling
results in the production of large quantities of steam, but the stream should be shut down before it disturbs the
thermal layering. The heat converts the water spray to steam, which fills the compartment and absorbs the bulk
of the heat. Once the fire has been darkened down and the space has been ventilated, the hose-lines can be
advanced to extinguish any remaining hot spots with a direct attack and water applied directly onto whatever is
burning.
Combination Attack
The combination attack method uses the heat-absorbing steam-generating technique of ceiling-level attack
cooling the hot gas layer combined followed by a heat-reducing with a direct attack on the materials burning near
the floor level. The attack starts with short bursts, known as penciling, from nozzle may be moved in a, T, Z, or O
pattern starting with a solid, straight, or a penetrating fog stream directed into the hot gas layer heated gases at
the ceiling level (gas cooling) (Figure 15.14). and then dropped down Then the attack switches to a straight
stream, known as painting, to attack the combustibles burning near the floor level. The O pattern of the
combination attack is probably the most familiar method of attack. When performing the O pattern, the stream
should be directed at the ceiling and rotated with the stream edge reaching the ceiling, wall, floor, and opposite
wall. Firefighters should keep in mind Remember that applying water to smoke does not extinguish the fire and
only causes unnecessary water damage and disturbance of the thermal layering
Essentials of Fire Fighting, Sixth Edition (IFSTA, 2013)
Chapter 17 Fire Control, Pages 1013-1016
(RED INDICATES CHANGES FROM FIFTH EDITION)


Direct Attack
The A direct attack on the fire using a solid or straight uses water most efficiently use of water
on free-burning fires (Figure 17.8) is made by a direct attack on the fire - usually from a solid
stream or straight stream. The water is applied in short bursts directly onto the burning fuels
(often called “penciling”) until the fire is extinguished “darkens down” (Figure 15.12). Another
effective technique (often called “painting”) is to direct the stream onto the ceiling and walls
cool hot surfaces which can to slow or stop the pyrolysis process on these hot surfaces by
gently applying water and allowing it to run over the hot material. Water should not be applied
long enough to upset the thermal layering (sometimes called thermal balance) in the
compartment; the steam produced will begin to condense, causing the smoke and heat to drop
rapidly to the floor and move sluggishly thereafter.
Indirect Attack
When firefighters are unable to enter a burning building or compartment because of the intense
heat inside, an indirect attack can be made from outside the structure or involved area
compartment through a window or other small opening (Figure 15.13). The attack is made
through a window or other opening, directing the stream toward the ceiling to cool the room
(Figure 17.9). This method of attack produces large quantities of steam and must be
coordinated with ventilation. is not ideal where building occupants may still be inside or where
the spread of fire to uninvolved areas cannot be contained. While an indirect attack cools the
fire environment, it results in a fairly uniform temperature from floor to ceiling and fills the
compartment with the combined mixture of smoke and steam. However, this may be the only
method of attack possible until temperatures are reduced.
To make an indirect attack on the fire, a fog stream is introduced through an small opening and
directed at the ceiling where the temperature is the highest heat is the most intense. The heat
converts the water spray to steam, which fills the compartment and absorbs the majority bulk of
the heat. Once the majority of the fire has been reduced in quantity darkened down and the
space has been ventilated, hoselines can be advanced inside and firefighters can make a
direct attack on the body of fire water applied directly onto whatever is burning.
Essentials of Fire Fighting, Sixth Edition (IFSTA, 2013)
Chapter 17 Fire Control, Pages 1013-1016
(RED INDICATES CHANGES FROM FIFTH EDITION)


Combination Attack
The combination attack uses the heat-absorbing technique of combines cooling the hot gas layer at the
ceiling level using an indirect attack with a followed by a heat-reducing direct attack on the materials fuels
burning near the floor level. The attack starts with short bursts, known as penciling, from a penetrating fog
stream directed into the hot gas layer at the ceiling level (gas cooling) (Figure 15.14). Then the attack
switches to a straight stream, known as painting, to attack the combustibles burning near the floor level.
To combine both attacks, move the nozzle from the area overhead to the floor in a Z, inverted T, or
rotational manner (Figure 17.10) Remember that applying Excessive application of water to smoke does
not extinguish the fire and only may causes unnecessary water damage and disturbance of the thermal
layering. Applying water to smoke that is not heated may disrupt the thermal layering which has a
tendency to decrease visibility if ventilation is not accomplished.
Gas Cooling
Gas cooling is not a fire extinguishment method but simply is a way of reducing the hazard presented by
heat release from the hot gas layer. This technique is effective when faced with a shielded fire; that is,
one you cannot see from the doorway because it is located in a remote part of the structure or objects are
shielding it the fire . In these situations, you cannot apply water directly onto the burning material without
entering the room and working under the hot gas layer.
The hot gas layer accumulating in the upper levels of the compartment can present a number of problems
for you and other members of the hoseline team crew. Remember that smoke is fuel, and it may transition
to rollover, flashover or a smoke explosion at any time. In addition, hot smoke radiates heat to furniture
and other combustibles in the compartment. This increases pyrolysis which adds more flammable fuel to
the gas layer. Cooling the hot gas layer mitigates these hazards by slowing slows the transfer of heat to
other combustibles and reducing reduces the chances of the overhead gases igniting.
You can To cool the hot gas layer, direct short bursts or by applying short pulses of water for into it. With
the nozzle set on a 40- to 60- degree fog pattern, direct it upward toward the gas layer and quickly and
smoothly open and close it in one- to two second pulses (Figure 17.11). The length of the pulse will
depend on the size of the space, varying from less than a second to much longer. The nozzle pattern may
need to be adjusted based on fire conditions in the compartment and its configuration and size. In narrow
hallways, the fog pattern may need to be restricted. In large-volume compartments or when the upper
layer temperature is extremely high, the duration of the pulses may need to be increased slightly.
The reach of the stream is also important for cooling the gas layer. Remember that Your intent is to cool
the gases, not to cool the ceiling produce a large volume of steam. Cooling the ceiling will produce a
large volume of steam. When If water droplets begin to fall out of the overhead smoke layer, it means that
the gases have been cooled and you can stop spraying water into the smoke. If the fire continues to burn
unchecked, the gas layer will regain its heat and the gas-cooling technique may have to be repeated.
The gas-cooling technique should be repeated as necessary while the hose team advances under the
gas layer toward the fire.
Essentials of Fire Fighting, Sixth Edition (IFSTA, 2013)
Chapter 17 Fire Control, Pages 1013-1016
(RED INDICATES CHANGES FROM FIFTH EDITION)
2013