Bs bab 2

FIRE PREVENTION AND PROTECTION

General Objective

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: To understand a systematic introduction to fire behavior,
prevention and control

Specific Objectives :
At the end of this unit you should be able to:
•

identify the causes of fire.

•

describe the types of fire prevention equipment and the system.

•

understand the fire prevention rules.

•

identify fire prevention symbols in building plans.


2.0

INTRODUCTION

What is a fire ?

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Fire are the largest accidental killer in Malaysia,
behind motor vehicle accidents, falls, and drowning.
It is also a disaster that families are mostly likely to
experience. Over 80 percent of all fire deaths occur
where people sleep, such as in homes or hotels. Most
fires occur when people are likely to be less alert
such as in homes or hotels and as between midnight
and morning. 84 percent of house and building fires
are accidental, such as those caused by poor
electrical wiring or negligence. However, 16 percent
are set intentionally through arson or acts of
terrorism.


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DID YOU KNOW?
Fires in buildings are nearly always man – made, resulting from error or
negligence. Primitive man used heat for cooking, warming and lighting his dwelling with
the inherent risk that misuse or accident in his control of fuel might precipitate disaster.
Today as in primitive society, that risk has not been eliminated despite the
apparent sophistication of modern living. With the development of habitation, attitudes to
fire protection or fire precautions also developed, sometimes subtly, but mostly from
bitter experience. The principal aims of fire precautions are simply to safeguard life and
property.
A fire extinguisher is a portable device used to put out fires of limited size. Such
fires are grouped into four classes, according to the type of materials that is burning.

Yes….I understand now, this unit will explore
the causes for the spreading of fire…I should
make a list of all I have to read today.


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WHAT CAUSES A FIRE?
Fire is a chemical reaction involving rapid oxidation or burning of a fuel. It needs three
elements to occur.

FUEL – Fuel can be any combustible material – solid, liquid or gas.
Most solids and liquids become a vapor or gas before they burn.

OXYGEN – The air we breathe is about 21 percent oxygen. Fire only
needs an atmosphere with at least 16 percent oxygen

HEAT- Heat is the energy necessary to increase the temperature of
the fuel to a point where sufficient vapors are given off for ignition
to occur.

CHEMICAL REACTION – A chain reaction can occur when the
three elements of fire are present in proper conditions and
proportions. Fire occurs when this rapid oxidation or burning takes
place.
Take any one these factors away, and a fire will not occur or will
be extinguished if it was already burning.


2.1

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Preventing The Causes For The Spreading Of Fire
a) Conduction
This is a process in which thermal energy can transfer through a solid or liquid that is
under the influence of a thermal stress or gradient. In most building materials it is a
molecular process by which the thermal energy can travel like a sound wave along a
solid. However, in the metallic material this energy transfer is caused by electron
movement within the solid material.

In building materials there are up to three distinct modes of energy transfer possible,
these being:

i-

Thermal conduction by atomic and molecular vibration
•

The ease at which thermal energy can be transferred down a rod or
other structure depends on the type of bonding between the molecules.

•

The materials that have a rigidly-bound structure pass more energy
than those with a weakly – bound structure.

•

This is due to the fact that the frequency of vibration for rigidly
molecules is high, thus the rate at which the energy is transferred is
also high. The energy is transmitted down the road by very-highfrequency elastic waves.


•

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These waves can be compared to sound waves, but have much higher
wave frequencies.

•

The quantum of energy associated with such wave motion is called the
phonon, which is passed from molecule in turn all the way down the
length of the rod.

•

In an insulation-type material, the conduction process is dominated by
these waves and their phonon-lattice framework collision processes.

•

So, if the interaction between phonons increases, as it must do with an
increase in temperature, this will cause the thermal conductivity.

•

Most masonry materials are polycrystalline, that is they consist of
more than one crystal type, and since the phonons are scattered by
crystal boundaries and by porosity it is not surprising that such
materials have a lower phonon-conductivity than the single-crystal
type.

•

The situation of an amorphous type material, such as glass, is one in
which the phonon-scattering process dominates thus making the
conductivity of an amorphous material independent of temperature for
practical purposes.

ii-

Thermal conduction due to radiation
•

Radiation passes through solids and undergoes scattering at structure
imperfections, crystal boundaries and at pores. In a highly porous


•

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material this type of conductivity can be shown to be proportional and
become quite significant at temperatures above 500

•

C.

However, in opaque-type materials this type of conductivity only starts
to become important at 1000

iii-





C or above.

Thermal conduction due to mass transfer ( gaseous conduction )
•

In this case a gas, such as air, which fills the pores within the material,
can add to the ability of the material to pass heat energy through the
material under a thermal gradient or by a buoyancy effect.


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Figure 2.1 : Thermal conduction routes within a building
structure

b) Radiation
This physical process unlike conduction or convection does not require a mechanical
medium to enable energy to be transferred from a hot radiant surface to a combustible
material.

Radiation, which may be in the ultra-violet, visible or heat radiation (infra-red) range,
is an electromagnetic wave.

Figure 2.2 : Sketch of rectangular radiations surface for work


c)

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Convection
The convection process plays a very important role in the spreading of fire

throughout a building since approximately 76 – 80 per cent of energy released from a
fire is by this process. In simple terms when a heat source is introduced to a fluid as
shown in figure 2.3 and 2.4.

Layer of gas close to ceiling

Figure 2.3 : Hot layer of gas forming at
ceiling level

Layer of hot gas

Figure 2.4 :

Radiation

feedback

from hot gas layer at ceiling to
combustible materials below


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Questions
1.

How does a fire start?

2.

List

the

causes

for

the

spreading of fire?
3.

What
process?

is

a

conduction


Answer
1.

Fire is a chemical reaction involving rapid oxidation or
burning of a fuel. It needs three elements to occur.

•

•
•

Fuel - fuel can be any combustible material,
example solid, liquid or gas. Most solids and
liquids become a vapor or gas before they
burn.
Oxygen – The air we breathe is about 21 percent
oxygen. Fire only needs an atmosphere with at
least 16 percent oxygen.
Heat – heat is the energy necessary to increase
the temperature of fuel to a point where
sufficient vapors are given off for ignition to
occur.

C3001 / UNIT 2 / 11


C3001 / UNIT 2 / 12

Answers
The causes are
•

conduction

•

radiation

•

convection

3. Conduction is a process in which thermal energy can transfer through a
solid or liquid that is under the influence of a thermal stress or gradient. In
most building materials it is a molecular process by which the thermal
energy travels like a sound wave along a solid.
However, in the metallic material energy transfer is caused by electron
movement within the solid material


2.2

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Type Of Fire Prevention Equipment And The System

HOW ARE FIRES
CLASSIFIED?

Fires are caused by the different materials, and thus classified into 4 categories:

CLASS A
Ordinary combustibles or fibrous material, such as
wood, paper, cloth, rubber and some plastics


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CLASS B
Flammable or combustible liquids such as
gasoline, kerosene, paint, paint thinners and
propane .

CLASS C
Energized

electrical

equipment,

such

as

appliance, switches, panel boxes and power
tools

CLASS D
Certain combustible metals, such as magnesium,
titanium, potassium and sodium. These metals burn
at high temperatures and give off sufficient oxygen
to support combustion. They may react violently
with water or other chemicals, and must be handled
with care.


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HOW ARE FIRES
PREVENTED?

Class A – Ordinary combustibles:
Keep storage and working areas free of trash. Place oily rags in
covered containers.

Class B – Flammable liquids or gases:
Don’t refuel gasoline-powered equipment in a confined space, especially in
the presence of an open flame such as a furnace or water heater.
Don’t refuel gasoline-powered equipment while it’s hot.
Keep flammable liquids stored in tightly closed, self-closing, spill-proof
containers. Pour from storage drums only what you’ll need.
Store flammable liquids away from spark-producing sources
Use flammable liquids only in well-ventilated areas.


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Class C – Electrical equipment
Look for old wiring, worn insulation and broken electrical fittings. Report any hazardous
conditions to your supervisor.
Prevent motors from overheating by keeping them clean an in good working order. A
spark from a rough-running motor can ignite the oil and dust in it.
Utility light should always have some type of wire guard over them. Heat from an
uncovered light bulb can easily ignite ordinary combustibles.
Don’t misuse fuses. Never install a fuse rated higher than specified for the circuit.
Investigate any appliance or electrical equipment that smells strange. Unusual odors can
be the first sign of fire.
Don’t overload wall outlets. Two outlets should have no more than 2 plugs.

Class D-Flammable metals:

Flammable metals such as magnesium and titanium generally take a very hot heat source
to ignite. However, once ignited they are difficult to extinguish as the burning reaction
produces sufficient oxygen to support combustion, even under water.


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In some cases, covering the burning metals with sand can help contain the heat and
sparks from the reaction. Class D extinguishing agents are available (generally as dry
powder in a bucket or box) which can be quite effective, but these agents are rare on the
campus.

If you are planning a research project using a large amount of flammable metals you
should consider purchasing a five or ten pound container of Class-D extinguishing agent
as a precaution.
Pure metals such as potassium and sodium react violently (even explosively) with water
and some other chemicals, and must be handled with care. Generally these metals are
stored in sealed containers in non-reactive liquid to prevent decay (surface oxidation)
from contact with moisture in the air.
White phosphorus is air-reactive and will burn / explode on contact with room air. It must
be kept in a sealed container with a non-reactive solution to prevent contact with air.
All of these metals are not uncommon in labs on the OU campus, but are generally only
found in small quantities. An accidental fire / chemical leading to a fire reaction can be
controlled or avoided completely through knowledge of the properties of the metals and
using good judgment and common sense.

HOW TO EXTINGUISH
SMALL FIRES ?


Class A - Extinguish ordinary combustibles by cooling the
material, below its ignition temperature and soaking the fibers to
prevent re-ignition. Use pressurized water, foam or multi-purpose
(ABC-rated) dry chemical extinguishers. DO NOT USE carbon
dioxide or ordinary (BC-rated) dry chemical extinguishers on class
A fires.

Class B - Extinguish flammable liquids, greases or gases by
removing the oxygen, preventing the vapors from reaching the
ignition source or inhibiting the chemical chain reaction. Foam,
carbon dioxide, ordinary (BC-rated) dry chemical, multi-purpose
dry chemical, and halon extinguishers may be used to fight Class B
fires.

C3001 / UNIT 2 / 18


Class C - Extinguish energized electrical equipment by using an
extinguishing agent that is not capable of conducting electrical
currents. Carbon dioxide, ordinary (BC-rated) dry chemical,
multi-purpose dry chemical and halon* fire extinguishers may be
used to fight Class C fires. DO NOT USE water extinguishers on
energized electrical equipment.
* Even though baton is widely used, EPA legislation is phasing it out
of use in favor of agents less harmful to the environment.

Class D - Extinguish combustible metals such as magnesium,
titanium, potassium and sodium with dry powder extinguishing
agents specially designated for the material involved. In most
cases, they absorb the heat from the material, cooling it below its
ignition temperature.
NOTE: Multipurpose (ABC-rated)

C3001 / UNIT 2 / 19


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Chemical extinguishers leave a residue that can harm sensitive equipment, such as computers
and other electronic equipment. Because of this, carbon dioxide or halon extinguishers are
preferred in these instances because they leave very little residue. ABC dry powder residue is
mildly corrosive to many metals. For example, residue left over from the use of an ABC dry
powder extinguisher in the same room with a piano can seriously corrode piano wires. Carbon
dioxide or halon extinguishers are provided for most labs and computer areas on campus.

HOW TO USE A PORTABLE
FIRE EXTINGUISHER?

Remember the acronym, "P.A.S.S."—
P ......Pull the Pin.
A …...Aim the extinguisher nozzle at the base of the
flames.
S …Squeeze trigger while holding the extinguisher
upright.
S

......Sweep the extinguisher from side to side,

covering the area of the fire with the extinguishing
agent.

REMEMBER……….


•

Should your path of escape be threatened

•

Should the extinguisher run out of agent

•

Should the extinguisher prove to be ineffective

•

C3001 / UNIT 2 / 21

Should you no longer be able to safely fight the fire

THEN LEAVE THE AREA IMMEDIATELY!

HOW DO YOU CHECK YOUR
FIRE EXTINGUISHERS?

1. Know the locations of the fire extinguishers in your work area.
2. Make sure the class of the extinguisher is safe to use on fires likely to occur in the
immediate area.
3. Check the plastic seal holding the pin in the extinguisher handle. Has the
extinguisher been tampered with or used before? Report any broken/missing
seals/pins to the Fire Safety Unit.
4. Look at the gauge and feel the weight. Make sure the extinguisher is full.


C3001 / UNIT 2 / 22

Water, some foam, and dry chemical extinguishers have gauges indicating the pressure
inside the extinguisher. The pressure needle should be in the "green" area (generally100-175
Ibs, depending on the type of agent).
CO2 (carbon dioxide) extinguishers are high pressure cylinders with pressures ranging from
1500 lb to 2150 Ib. These extinguishers DO NOT have gauges and must be weighed by fire
Safety Unit staff to determine the amount of contents remaining.

NOTE :Ib and Ibs = pounds

5. Make sure the pin, nozzle and nameplate are intact.
6. Report any missing, empty or damaged fire extinguishers to the Fire Safety Unit
whenever you notice any discrepancies.

2.2.1 Description Of Fire Extinguishers: How Do They Look Like?
Generally, you can tell at a glance which type an extinguisher is hanging on the
wall, or in the cabinet, just by looking at its shape. Check the labels of the extinguishers
in your area and note the color and shape/size of the extinguisher. This may help if
someone runs in to help you fight a fire with the WRONG extinguisher (i.e. water on an
electrical fire) - you can STOP them before they are injured or make matters worse!

ABC-rated multipurpose dry powder extinguishers are the most
common on campus, particularly in the corridors of academic buildings.
They are almost always RED in color and have either a long narrow
hose or no hose (just a short nozzle). These extinguishers are very light
(5-25 Ibs total weight).Halon extinguishers look virtually identical to
ABC multipurpose dry chemical extinguishers.


C3001 / UNIT 2 / 23

Water extinguishers are generally only found in the dormitories and are
usually SILVER (crome-metal) in color, have a flat bottom, have a long
narrow hose, are quite large (2-1/2 gallons). Foam extinguishers (rare on
the OU campus, nowadays) look similar and the type without gauges
have a handle inset in the flat bottom (you turn the extinguisher upside
down to start and use it)

C02 (carbon dioxide) extinguishers are generally red (often
yellow around aircraft or on military sites), have a LARGE
"tapered" nozzle (horn), are VERY HEAVY (15-85 Ibs.)Some
CO2 extinguishers for aircraft hangers or special industrial use
are so large as to require roll-around carts to move them. These
are all high-pressure cylinders.
Care should be taken not to drop a CO2 cylinder; if it is
damaged it may be able to make a hole through the nearest
wall(s) and end up on the other side of campus! (The
containers are quite sturdy, but don't abuse them.) 002
cylinders do not have a pressure gauge – they must be weighed
to determine the amount of contents


C3001 / UNIT 2 / 24

WHERE can I find a
fire extinguisher on
campus?

•

In the corridors of academic and office buildings, and inside very large rooms

•

In or immediately outside all laboratories where chemicals are stored and used

•

In or immediately outside mechanical spaces where motorized or other equipment
is present which might reasonably cause a fire

•

In campus airpark hangers, storage buildings, and mounted inside certain university
vehicles

Questions
State whether the following statement are TRUE or
FALSE
1.

Do not use carbon dioxide or ordinary dry
chemical extinguishers on class A fires.

2.

Class A fires are fueled by ordinary
combustible or fibrous material, such as
wood, paper, cloth and some plastics.

3.

Class D fires can be extinguished with
water.


C3001 / UNIT 2 / 25


Answers
1.

True

2.

True

3.

False

C3001 / UNIT 2 / 26


2.3

C3001 / UNIT 2 / 27

Fire prevention rules
People protect themselves from the dangers of fires in several ways. Fire

extinguishers in homes enable people to put out fires before they become dangerous,
while smoke detectors alert residents that a fire has broken out in the early stages.

Hundreds of Malaysians die in home and building fires each year, but most of
these deaths could be avoided. Make sure your family knows simple fire-prevention rules
and what to do if a fire does strike.

Most fire victims die from inhaling smoke and poisonous gases, not from burns. If
you know how to recognize danger signs and how to act appropriately, you will increase
your chances of getting safely out of a burning building.

2.3.1 Fire – Safety Procedure

Have a plan set in advance. All rooms in your house should have two means of
escape. Draw a picture showing the escape routes for every room and explain it to
everyone.
Upper floor windows should have hook-on fire escape ladders or rope ladders.
Assign one older person to be responsible for each child. Plan on a meeting place
outside.


C3001 / UNIT 2 / 28

Have practice fire drills every three months, especially if there are small children or
disabled persons in your home. Some of your drills should take place at night.
All members of the family should know how to call 911 to give the house address and
tell the person on duty that there is a fire.

2.3.2 Warning From The Smoke Detector Alarms

Act immediately but try to stay calm. Wake up anyone who may still be asleep, and
shout, "Fire! Everyone out!" Don't waste time getting dressed or searching for valuables.
Once outside the house, do not go back in.
Sleep with bedroom doors closed. Doors offer protection from heat and smoke and slow
a fire's progress. If in your escape you must go from room to room, close each door
behind you.

Feel every door before opening it. Place the back of your hand on the crack between the
door and the door frame; if it's hot, do not open the door. Even if the door is cool, open it
cautiously. Stay low in case smoke or toxic fumes are seeping around the door. If heat
and smoke come in, slam the door tightly and use alternative exits.
If you use a window for your escape, be sure the door in the room is closed tightly.
Otherwise, the draft from the open window may draw smoke and fire into the room.
If you must go through smoke, crawl under it on your hands and knees. However, do not
crawl on your belly, because some heavier toxic gases settle in a thin layer on the floor.
If you are unable to escape from a room because of a fire on the other side of the door,


C3001 / UNIT 2 / 29

stuff clothing, towels, or newspapers in the door's cracks to keep smoke out of your
refuge.
Remember "STOP, DROP, ROLL" if your clothing catches fire. The moment it
happens, stop where you are. Drop to the ground, and cover your mouth and face with
your hands to protect them from the flames. Then roll over and over to smother the
flames.

2.3.3 High Rise Apartments
If you live in a high rise apartment there are a few added things you should know in case
there is a fire in your building:
Learn your building's evacuation plans. Know the location of fire alarms, and learn how
to use them. Post emergency fire department numbers near all telephones.
If you hear instructions on your building's public-address system, listen carefully and do
just as you're told.
Never take an elevator when leaving a burning building. Instead, go directly to the
nearest fire- and smoke-free stairway.
If you cannot get to a fire stairway, go to a room with an outside window.
If there is a working phone, call the fire department emergency number and tell the
dispatcher where you are. Do this even if you can see fire trucks on the street below.


C3001 / UNIT 2 / 30

Stay where rescuers can see you through the window, and wave a light-colored cloth
such as a hand towel to attract their attention.
If possible, open the window at the top and bottom. Be ready to shut the window quickly
if smoke rushes in.
You may need to be patient; the rescue of occupants of a high-rise building can take
several hours.

DO

YOU

BUILDING

KNOW

WHAT

REGULATIONS

ARE?

2.3.4 Building Regulations
The current set of building regulations have their origin in Post-War Building
Studies and the objectives, although never expressly stated, have experienced a subtle
change of emphasis in order to remain relevant to a modern social and industrial
infrastructure. In this chapter it is intended to discuss the philosophy of the current
prescriptive building regulations.


C3001 / UNIT 2 / 31

Building regulations assume that if certain components of fire safety can be
identified and suitable standards applied to particular building types, a satisfactory level
of fire safety will be achieved.

There is no evidence to support this assumption. Indeed, some would argue that
the available evidence points in the opposite direction. Generally the structure of building
regulations follow the pattern developed below:

1. Classify buildings by type
2. Compartment buildings
3. Prescribe fire resistance requirements for elements of structure
4. Limit unprotected areas of external walls
5. Prescribe constructional requirement for separating walls, compartment walls and
floors.
6. Prescribe constructional requirements for protected shafts
7. Specify the type and constructional requirements for fire-resisting doors
8. Control the penetration of fire barriers by services
9. Specify non-combustibility requirements for stairways in prescribed situations
10. Describe requirements for cavity barriers and fire stops
11. Control spread of flame over walls and ceilings
12. Control the use of plastics on ceilings
13. Relate the sitting of buildings to roof constructional requirements.


C3001 / UNIT 2 / 32

2.4 Fire Prevention Symbols In Building Plan


C3001 / UNIT 2 / 33

SOURCE: BUILDING AND FIRE T.JSHIELD & G.W.H.SILCOCK LONGMAN SCIENTIFIC
& TECNICAL


C3001 / UNIT 2 / 34

Questions
1.

What would you do if someone is on fire?

2.

What would you do if you are trapped in a building
which is on fire?


Answer
1. In situation when a person is on fire :
STOP

-

where you are

DROP

-

to the floor

ROLL

-

around on the floor

C3001 / UNIT 2 / 35


2. These are the steps that you need to follow:
•

Act immediately but try to stay calm

•

If you use a window for your escape, be sure
the door in the room is closed tightly.

•

If in a dorm room, use wet towels to seal the
space under the door and prevent the entry
of smoke.

Write the best answer for each of the following questions:

C3001 / UNIT 2 / 36


C3001 / UNIT 2 / 37

1.

How do you use a portable fire extinguisher?

2.

How are fires classified?

3.

How are fire extinguishers classified?

Mistake shows us what we
need to learn


1.

C3001 / UNIT 2 / 38

Remember the acronym “ P. A .S . S ”

P………..Pull the pin
A……….Aim the extinguisher nozzle at the base of the flames
S………..Squeeze trigger while holding the extinguisher upright
S………..Sweep the extinguisher from side to side, covering the area of the
fire with the extinguisher agent
2.

The 4 classes of fires are :
•

Class A – caused by ordinary combustible liquid such as gasoline,
kerosene, paint thinners and propane.

•

Class B – caused by flammable or combustible liquids such as gasoline,
kerosene, paint thinners and propane.

•

Class C – caused by energized electrical equipment, such as appliance,
switches, panel boxes and power tools.

•

Class D – caused by certain combustible metal, such as magnesium,
titanium, potassium and sodium. These metal burn at high temperatures
and give off sufficient oxygen to support combustion.

•

They may react violently with water or other chemicals, and must be
handled with care.


3.

C3001 / UNIT 2 / 39

Fire extinguishers are classified by the size and class of the fire; they are
designed to extinguish fires. Different extinguishing agents are used for
different classes of fire.

Pass" and "fail" are the
old ways of explaining
how

much

you

know. The

new ways are, "knowledge
and "ignorance".

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