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In this chapter you will learn about: |
Fire chemistry
How fire occurs,
classes of fire, and choosing the correct means to extinguish each type of fire. |
Hazardous materials
How to identify potentially
dangerous materials in storage or in transit. |
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Fire hazards
Potential fire hazards in the
home and worksite, and fire prevention strategies.
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Fire suppression strategy
How to evaluate
fires, assess firefighting resources, and determine a course of action. |
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Portable fire extinguishers
Types of
portable fire extinguishers and how to operate them.
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Safe fire suppression
How to decide if you
should attempt to extinguish a fire; how to approach and extinguish a fire
safely. |
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Teamwork
The importance of working with a
buddy.
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Introduction
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During and immediately after a disaster, the first priorities
of professional fire services are life safety and extinguishing major
fires. They may be hampered by impassable roads, inadequate water supply,
weather conditions, burning material, and inadequate resources to deal with the
number of existing major fires.
At this time, CERT fire suppression groups play
a very important role in firefighting and fire prevention by:
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Putting out small fires before they
become major fires
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Preventing additional fires by
removing fuel sources
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Assisting with evacuations where necessary
Portable fire extinguishers are an invaluable firefighting
tool. They can be used to eliminate small fires that might otherwise grow into
larger, more destructive fires and to prevent the loss of life and property.
Potential fuel sources include natural gas and electrical
utilities as well as hazardous materials. Understanding hazardous materials and
other fire hazards in the home and workplace will help you determine the
appropriate course of action to take.
Work with a buddy.
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Fire Chemistry |
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Fires require three elements to exist:
Heat. The temperature at which a material
produces a vapor, and the temperature at which vapors will burn. (Vapors will
self-ignite if the temperature is hot enough.)
Fuel. The fuel for a fire may be a
solid, liquid, or gas. The type and quantity of the fuel will determine which
method should be used to extinguish the fire.
Oxygen. Fires will burn vigorously in
any atmosphere of at least 20 percent oxygen. Without oxygen, fuel could be
heated until entirely vaporized, and it would not burn.
Together, these three elements are called the fire
triangle
See
the Fire Triangle
The three elements in the proper proportions will produce
fire. Extinguishment is possible when one of the three elements is missing as
shown in the following figure.

Figure II-2. Effect Of Removing Elements Of The Fire Triangle
Classes of fire are based on the type of fuel that is
burning. There are four major classes of fire:
Class A. Ordinary combustibles such as
paper, cloth, wood, rubber, and many plastics.
Class B. Flammable liquids (e.g.,
oils, gasoline, kitchen grease, paints, and solvents) and combustible liquids
(e.g., charcoal lighter, kerosene, and diesel fuel). These fuels burn only at
the surface because oxygen cannot penetrate the depth of the fluid. If
ignited, it is the vapor that burns.
Class C. Electrical equipment (wiring, fuse
boxes, motors, power tools, appliances).
Class D. Combustible metals such as aluminum,
magnesium, and titanium.
It is extremely important to identify the type of fuel so
that the correct method and agent can be used to extinguish the fire.
The remainder of this chapter will deal with:
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CERT size-up.
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Firefighting resources.
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Safe fire suppression
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Hazardous Materials
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What Are Hazardous Materials?
Hazardous materials are any materials that corrode other
materials, explode or are easily ignited, react strongly with water, are
unstable when exposed to heat or shock, or are otherwise toxic to humans,
animals, or the environment. Hazardous materials include, but are not limited
to:
Hazardous materials pose an ever-present danger. They are
stored in all types of locations, and they are transported by a variety of
means. They are commonly found in such places as industrial and commercial
districts, highways, harbors, airports, and railroads. They are also found in
homes and offices.
Identifying Stored Hazardous Materials
Stored hazardous materials may be identified by means of the
National Fire Protection Association (NFPA) 704 Diamond system of placards.
These placards are located on the outside of buildings at the entrance to the
storage area. An example of the NFPA 704 Diamond is shown in the following
figure.
See
the National Fire Protection Association 704 Diamond
The diamond is divided into four colored quadrants, each with
a rating number inside it. The colored quadrants provide information about the
type of danger caused by the material. The numbers within the red, blue, and
yellow quadrants (provided for professional firefighter use only) indicate the
degree of risk associated with the material. Consider these placards a
"stop sign" for CERT members, unless in your planning stages you
have identified the dangers involved.
Identifying Hazardous Materials In Transit
Hazardous materials that are being transported are marked
with Department of Transportation (DOT), United Nations (UN), or North American
(NA) warning placards. For the DOT system, each diamond-shaped placard includes
a color, symbol, name, and number, each of which indicates the type of hazard.
See the DOT Warning Placards
What can you do about fire hazards in the home or office?
Simple fire prevention practices will
Reducing
Hazards In Home And Office
go far in reducing the likelihood of fires. First, locate
potential sources of ignition. They may include electrical hazards, natural gas
hazards, and flammable or combustible liquids. Then do what you can to reduce
or eliminate fire hazards. This section will address the elimination of
hazards related to:
Electrical Hazards
When misused or neglected, electricity can cause serious
injury or death. With a little effort, however, most electrical hazards can be
eliminated. Ways to reduce electrical hazards include:
- Avoid the "electrical octopus." Eliminate tangles
of electrical cords and dont overload electrical outlets.
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Dont run electrical cords under carpets.
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Replace broken or frayed cords immediately.
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Properly maintain electrical appliances. Remove or replace
malfunctioning appliances.
When an electrical emergency does occur, be prepared to
handle an electrically charged appliance fire. Know where the power shut-off and
circuit breakers or fuses are, and know how to shut off the power.
■ For circuit boxes: Switch off smaller breakers first, then
the main breaker.
■ Fuse boxes:
Unscrew the individual fuses, then pull the main switch.
Examples of circuit and fuse boxes are shown in the figures
below. Do not, however, enter a flooded basement to shut off the
electrical supply.

Figure II-7. Circuit B Box Figure II-8. Fuse Box
When turning power back on, turn the main breaker
or switch on first, then switch on the smaller breakers or fuses.
Natural Gas Hazards
Natural gas presents two kinds of hazards. It is an asphyxiant,
meaning that it robs the body of oxygen, and it is explosive leaking gas
can easily be ignited, causing an explosion and subsequent fires. Ways to reduce
natural gas hazards in a disaster include:
Installing a gas detector near your furnace and hot water
heater and testing the detector monthly to ensure that it works.
Locating and labeling the gas shut-off valve. (Multiple gas
units in an apartment building are usually identified by apartment number or
letter.) NOTE: After the natural gas is turned off, it should be turned
on only by a trained utility technician.

Figure II-9. Natural Gas Meter With Shut-Off
Knowing how to shut off the gas. The valve position
indicates ON/OFF.
NOTE: Never enter the basement of a structure
that is on fire to turn off any utility.
Having the proper tool (gas wrench, pliers, channel locks,
ViseGrips, etc.) in your disaster supplies kit or near the gas valve.
Strapping the water heater to the wall in two places:
? from the top and ? from the bottom of the tank. Each strap
should cross behind the water tank and fasten to wall studs behind the tank.
(See Figure II-10 below.)
Have a licensed plumber attach the water heater to the gas
supply by a flexible gas line with shut-off that will move in the event of an
earthquake.
See
Hot Water Heater Bracing
Flammable Liquid Hazards
Many typical household products, such as gasoline, charcoal
lighter, and paint thinners and removers are flammable. In addition, many
household products such as air fresheners, deodorants, hair sprays,
insecticides, and furniture polish are packaged as aerosols. Aerosols contain
flammable propellants and may explode if heated.
To minimize hazards associated with flammable products:
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Read labels to identify flammable
products.
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Store them properly (remember the L.I.E.S.
rules Limit, Isolate, Eliminate, Separate).
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CERT Size-Up |
Before fire suppression operations can begin, rescue teams
must first ensure the safety of all rescuers, then citizen life safety. Once
these primary concerns have been addressed, CERT size-up can begin.
The first task in fire suppression is the size-up or
gathering of information for decision making and planning. Size-up is a
continuous data-gathering process that will dictate whether to attempt fire
suppression, and planning for extinguishing the fire. CERT size-up answers these
questions:
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Can my buddy and I fight the fire safely?
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Do my buddy and I have the right equipment?
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Are there other hazards?
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Is the building going to collapse?
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Can my buddy and I escape?
Some of the factors involved in each step of size-up are
shown in the checklist on the following pages. Use the checklist as a guide for
CERT size-up. Taking the actions listed will help the CERT member make safer
decisions. Practice will make this process more automatic.
◦ How?
Weather
◦ If yes, how will the fire situation be impacted?
Type Of Construction
◦ What type(s) of structure(s) are involved?
◦ What type(s) of construction are involved?
Occupancy
◦ If yes, how many people are likely to be affected?
Hazards
◦ If yes, what other hazards?
Step 1: Gather Facts
Time
◦ Does the time of day or week impact fire suppression
efforts?
◦ How?
Weather
◦ Will weather conditions impact your safety?
◦ If yes, how will your safety be impacted?
◦ Will weather conditions impact the fire suppression?
◦ If yes, how will the fire situation be impacted?
Type of Construction
◦ What types of structures are involved?
◦ What types of construction are involved?
Occupancy
◦ Are the structures occupied?
◦ If yes, how many people are likely to be affected?
◦ Are there special considerations (e.g. children, elderly)
Hazards
◦ Are hazardous materials involved?
◦ Are any other types of hazards likely to be involved?
◦ If yes, what other hazards?
Step 2: Assess And Communicate The Damage
◦ Take a lap around the building. Is the damage beyond the CERT teams
capability?
◦ If yes, what special requirements or qualifications are required?
Step 3: Consider Probabilities Yes / No
Life Hazards
◦ If yes, what are the hazards?
Path Of Fire
◦ What is the path of the fire?
◦ If yes, what other areas may be jeopardized?
Additional Damage
◦ Will it impact personal safety?
Step 4: Assess Your Own Situation
◦ What resources are available with which you can suppress the fires?
◦ What equipment is available?
Step 5: Establish Priorities
◦ If no, do not attempt suppression.
◦ Are there other, more pressing needs at the moment
◦ Can fire suppression be safely attempted by CERT members?
Step 6: Make Decisions
◦ Where will deployment of available resources do the most good while
maintaining an adequate margin of safety?
Step 7: Develop Action Plans
◦ Determine how personnel and other resources should be deployed.
Step 8: Take Action
◦ Put the plans into effect.
Step 9: Evaluate Progress
Continually size up the situation to identify changes in the:
◦ Scope of the problem
◦ Safety risks
◦ Resource availability
Adjust strategies as required.
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Firefighting Resources |
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A variety of resources may be available for fire suppression,
including:
Portable Fire Extinguishers. Portable
fire extinguishers are an invaluable tool for putting out small fires. A
well-prepared home or office will have at least two.
Interior Wet Standpipes. In commercial
buildings and apartment buildings, interior wet standpipes should be available
for use by occupants or tenants. These standpipes usually consist of about 100
feet of 1?-inch jacketed hose with a 3/8-inch nozzle tip. They deliver
up to 125 gallons of water per minute. NOTE: Always work in
3-person teams when using an interior wet standpipe. One person handles the
hose, another bleeds the air from the line, and the third controls the water
pressure.
Confinement. In interior spaces, the ability
to confine the fire by closing doors is a valuable resource. Close doors to
rooms and hallways to restrict the spread of smoke and heat while you escape
to the outside.
"Creative" Resources.
Sometimes it is necessary to make use of other materials and equipment that
may be at hand. Examples include:
◦ Swimming pool or spa, with buckets
◦ Dirt or sand and shovels
◦ Garden hose and ladders (for second floor or roof)
The type of fuel will determine which firefighting agent(s)
you select.
This section will focus on portable fire extinguishers, as
they are the most likely resource available in an emergency.
Extinguisher Rating And Labeling
Portable fire extinguishers must be rated and approved by the
State Fire Marshal and Underwriters Laboratories. They are rated according to
their effectiveness on classes of fire and their relative strength and
capability and must be so labeled by the manufacturer.
See
a Manufacturers Label
Each manufacturers label also displays the NFPA rating
code for the extinguisher. The rating provides important information about the
types of fires that can be extinguished using the extinguisher.
Types Of Fire Extinguishers
There are five types of extinguishers:
◦ Water Dry chemical Halon Carbon dioxide Foam
It is extremely important to use the correct agent and method
for the class of fire. The chart in
Figure II-12 on the following page shows
appropriate agents and methods for each type of fire.
The characteristics of
each type of fire extinguisher are listed below and on page II-25.
Water Extinguishers
Water extinguishers are among the most commonly used. They
are excellent for heat removal on Class A fires. Extreme caution should be
exercised when using a water extinguisher to ensure that the water, which is
under extreme pressure, does not scatter lightweight materials and spread the
fire.
Common characteristics for water fire extinguishers are:
◦ Capacity. Standard size is 2 gallons.
◦ Range. 30-40 feet.
◦ Pressure. 110 pounds per square inch (psi).
Fire
Types, Extinguishing Agents, And Methods
Dry Chemical Extinguishers
Dry chemical extinguishers are also commonly used. Regular
dry chemical extinguishers have a sodium bicarbonate base and are effective on
Class B and C fires. Multipurpose dry chemical extinguishers have a monoammonium
phosphate base and are effective for Class A, B, and C fires. Both types of dry
chemical extinguishers are nontoxic. Both should be inverted monthly to prevent
caking. Common characteristics for dry chemical extinguishers are:
◦ Capacity. Approximately 10-20 seconds discharge
time.
◦ Range. 8-12 feet.
◦ Pressure. 175-250 psi.
Other Types Of Extinguishers
Although still in use, carbon dioxide, halon, and foam
extinguishers are becoming less common.
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Carbon Dioxide Extinguishers
are
used primarily on Class C fires and are also effective on Class B fires. They
have limited use on Class A fires because of reflash potential. They suppress
fire by displacing or diluting oxygen levels.
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Halon Extinguishers
are best used
on Class B or C fires. Halon is a clean agent and is nontoxic when used in low
concentrations or in non-confined areas. However, halon extinguishers are being
phased out because of potential impact on the environment.
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Foam Extinguishers
are used for
special applications and are less common.
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Deciding To Use A Fire Extinguisher |
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Below is a decision making guide for using a portable fire
extinguisher during a fire in a disaster.
Ask yourself each of the questions
before attempting to extinguish a fire. If you answer "NO" to any of
these questions:
◦ Leave the building immediately.
◦ Shut all doors as you leave to slow the spread
of the
fire.
If you answer "YES" to all of the questions, you
may attempt to extinguish the fire.
If you feel unable to extinguish the fire,
however, leave immediately.

Courtesy of Public Education Specialist, City of
Colorado Springs Fire Department
Figure II-13. Deciding To Use A Fire Extinguisher
Operating A Fire Extinguisher
A portable fire extinguisher includes the following
components:
These components are shown in the figure below.
Figure II-14. Components Of A
Portable Fire Extinguisher
Always operate extinguishers in an upright position. As shown
in the figure below, the acronym to remember when operating a portable
extinguisher is P.A.S.S.:
Pull,
Aim,
Squeeze,
Sweep. Aim at the base of the
fire.

Figure II-15. P.A.S.S.
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Fire Suppression Safety |
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As in all emergency operations, safety is key when fighting
fires. CERT teams should use the following guidelines when approaching and
suppressing a fire.
- Do not attempt to suppress a fire that is clearly too large for the
equipment at hand.
- Use safety equipment (helmet, goggles, dust mask, all-leather work gloves,
heavy shoes).
- Work in a buddy system.
- Have a backup team when possible.
- Always have two ways to exit the fire area.
- Approach smoke-filled areas correctly. The primary component of smoke is
carbon monoxide. Without proper self-contained breathing apparatus,
firefighting will be limited. Use extreme caution when entering smoke-filled
areas.
1) Feel closed doors with the back of the hand, working from
the bottom of the door up. If the door is hot, there is fire behind it.
2) Confine the fire whenever possible by keeping doors closed.
3) Stay low to the ground.
4) Always know a second escape route.
5) Use natural ventilation techniques to clear smoke:
◦ Open
windows if possible
◦ Create cross-ventilation by channeling natural wind
flow.
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Maintain a safe distance. Remember the effective
extinguisher range.
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Move around the perimeter of the fire to maximize coverage
of the extinguisher agent.
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Overhaul ensures that every piece of burning material is completely
extinguished. To prevent rekindling of the fire:
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Locate hidden burning material. Extinguish and safely remove it.
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Remove heat by cooling.
H ALWAYS Wear safety equipment:
| ■ Helmet |
■ Goggles |
■
Dust mask |
■ Gloves |
■ Boots |
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Summary |
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Effective fire suppression depends on an understanding of:
◦ The elements
required for fire to exist
◦ The class of fire
◦ The type of material involved
◦ The resources required to extinguish
each type of fire
◦ Fire suppression techniques
The Fire Triangle
Fires require three elements to exist:
If any of the elements are missing or can be suppressed, the
fire can be extinguished.
Classes Of Fire
There are four types of fire:
Class A. Ordinary combustibles.
Class B. Flammable liquids.
Class C. Electrical equipment.
Class D. Combustible metals.
It is extremely important to identify the class of fire so
that you can select the proper means of extinguishing the fire.
Hazardous Materials
To help understand the types of materials, several
organizations have developed placarding systems for hazardous and non-hazardous
materials being stored or transported.
The NFPA 704 diamond system uses a combination of colors
and numbers to placard stored materials according to the type of hazard and
level of danger they present.
Several organizations have developed placarding systems for
transported materials:
◦ Like the NFPA 704 diamond, the DOT placard uses
numbers and colors to identify placard-transported materials
according to
type of hazard and level of danger.
◦ UN and NA placards use numbers to identify specific
types
of hazards.
When approaching accidents involving materials that are
placarded as hazardous or when the material is unknown keep away and call
for professional help immediately. Do not attempt to deal with the
hazard yourself. NFPA 704 Diamond system and UN and NA placards are
"STOP
SIGNS" to CERT teams.
Firefighting Resources
While there are many resources available for extinguishing
fires, the resource that you will use most frequently is the portable fire
extinguisher. Portable extinguishers are labeled according to:
◦ The class(es) of the fire against which they are effective.
◦ The fire area that they can suppress.
Water and dry foam extinguishers are the most commonly used.
Water extinguishers are effective for Class A fires. Regular dry foam
extinguishers are effective for Class B and C fires. Multipurpose dry foam
extinguishers, however, are effective for Class A, B, or C fires.
Other types of portable fire extinguishers that are less
commonly used are carbon dioxide extinguishers, halon extinguishers, and foam
extinguishers.
Fire Suppression Techniques
When using a portable fire extinguisher, remember to use the
P.A.S.S.
method:
Pull, Aim, Squeeze, Sweep. You will have the opportunity to practice
using a portable fire extinguisher during the classroom session.
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