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C3001 / UNIT 2 / 1FIRE PREVENTION AND PROTECTION
General Objective : 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.
C3001 / UNIT 2 / 2FIRE PREVENTION AND PROTECTION
2.0 INTRODUCTION
What is a fire ?
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.
C3001 / UNIT 2 / 3FIRE PREVENTION AND PROTECTION
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.
C3001 / UNIT 2 / 4FIRE PREVENTION AND PROTECTION
WHAT CAUSES A FIRE?
Fire is a chemical reaction involving rapid oxidation or burning of a fuel. It needs three
elements to occur.
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.
FUEL – Fuel can be any combustible material – solid, liquid or gas.
Most solids and liquids become a vapor or gas before they burn.
C3001 / UNIT 2 / 5FIRE PREVENTION AND PROTECTION
2.1 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-high-
frequency elastic waves.
C3001 / UNIT 2 / 6FIRE PREVENTION AND PROTECTION
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
C3001 / UNIT 2 / 7FIRE PREVENTION AND PROTECTION
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 C or above.
iii- 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.
Figure 2.1 : Thermal conduction routes within a building structure
C3001 / UNIT 2 / 8FIRE PREVENTION AND PROTECTION
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
C3001 / UNIT 2 / 9FIRE PREVENTION AND PROTECTION
c) 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.
Figure 2.3 : Hot layer of gas forming at
ceiling level
Figure 2.4 : Radiation feedback
from hot gas layer at ceiling to
combustible materials below
Layer of gas close to ceilingLayer of hot gas
C3001 / UNIT 2 / 10FIRE PREVENTION AND PROTECTION
Questions
1. How does a fire start?
2. List the causes for the
spreading of fire?
3. What is a conduction
process?
C3001 / UNIT 2 / 11FIRE PREVENTION AND PROTECTION
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 / 12FIRE PREVENTION AND PROTECTION
Answers
2. 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
C3001 / UNIT 2 / 13FIRE PREVENTION AND PROTECTION
2.2 Type Of Fire Prevention Equipment And The System
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
HOW ARE FIRES
CLASSIFIED?
C3001 / UNIT 2 / 14FIRE PREVENTION AND PROTECTION
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.
C3001 / UNIT 2 / 15FIRE PREVENTION AND PROTECTION
Class A – Ordinary combustibles:
Class B – Flammable liquids or gases:
Keep storage and working areas free of trash. Place oily rags in
covered containers.
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.
HOW ARE FIRES
PREVENTED?
C3001 / UNIT 2 / 16FIRE PREVENTION AND PROTECTION
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.
C3001 / UNIT 2 / 17FIRE PREVENTION AND PROTECTION
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 ?
C3001 / UNIT 2 / 18FIRE PREVENTION AND PROTECTION
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 / 19FIRE PREVENTION AND PROTECTION
NOTE: Multipurpose (ABC-rated)
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.
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.
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.
C3001 / UNIT 2 / 20FIRE PREVENTION AND PROTECTION
REMEMBER……….
Should your path of escape be threatened
Should the extinguisher run out of agent
Should the extinguisher prove to be ineffective
Should you no longer be able to safely fight the fire
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.
HOW TO USE A PORTABLE
FIRE EXTINGUISHER?
C3001 / UNIT 2 / 21FIRE PREVENTION AND PROTECTION
THEN LEAVE THE AREA IMMEDIATELY!
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.
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.
HOW DO YOU CHECK YOUR
FIRE EXTINGUISHERS?
C3001 / UNIT 2 / 22FIRE PREVENTION AND PROTECTION
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.
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)
C3001 / UNIT 2 / 23FIRE PREVENTION AND PROTECTION
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
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
WHERE can I find a fire extinguisher on campus?
C3001 / UNIT 2 / 24FIRE PREVENTION AND PROTECTION
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 / 25FIRE PREVENTION AND PROTECTION
Answers
1. True
2. True
3. False
C3001 / UNIT 2 / 26FIRE PREVENTION AND PROTECTION
2.3 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
C3001 / UNIT 2 / 27FIRE PREVENTION AND PROTECTION
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.
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
C3001 / UNIT 2 / 28FIRE PREVENTION AND PROTECTION
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, 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
C3001 / UNIT 2 / 29FIRE PREVENTION AND PROTECTION
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.
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.
C3001 / UNIT 2 / 30FIRE PREVENTION AND PROTECTION
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.
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:
DO YOU KNOW WHAT
BUILDING REGULATIONS ARE?
C3001 / UNIT 2 / 31FIRE PREVENTION AND PROTECTION
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.
2.4 Fire Prevention Symbols In Building Plan
C3001 / UNIT 2 / 32FIRE PREVENTION AND PROTECTION
SOURCE: BUILDING AND FIRE T.JSHIELD & G.W.H.SILCOCK LONGMAN SCIENTIFIC & TECNICAL
C3001 / UNIT 2 / 33FIRE PREVENTION AND PROTECTION
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?
C3001 / UNIT 2 / 34FIRE PREVENTION AND PROTECTION
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 / 35FIRE PREVENTION AND PROTECTION
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.
C3001 / UNIT 2 / 36FIRE PREVENTION AND PROTECTION
Write the best answer for each of the following questions:
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
C3001 / UNIT 2 / 37FIRE PREVENTION AND PROTECTION
1. 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.
C3001 / UNIT 2 / 38FIRE PREVENTION AND PROTECTION
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. 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".