Fire is the rapid oxidation of a material through the exothermic chemical process of combustion, releasing heat, light, and reaction products. Combustion requires an oxidant, fuel, and heat in a chemical reaction. There are two types of combustion - complete and incomplete. Fire spread occurs through conduction, convection, and radiation as heat transfers between materials. There are different classes of fire based on the type of fuel - Class A involves ordinary combustibles, Class B involves flammable liquids, Class C involves energized electrical equipment, Class D involves combustible metals, and Class K involves vegetable/animal oils in commercial cooking equipment. Controlled and uncontrolled fires are distinguished by the level of control over fire properties like size,

2. Presentation on
FIRE
Name: R.K.M. Raju Ahammed
ID: 2013100400004
BATCH:23rd
SOUTHEAST UNIVERSITY

3. WHAT IS FIRE?
 Fire is rapid oxidation of a material in the exothermic
chemical process of combustion, releasing heat, light,
and various reaction products.
 Slower oxidative processes like rusting or digestion are
not included by this definition.

4. CHEMISTRY
 Combustion is a high-temperature exothermic redox
chemical reaction between a fuel and an oxidant, usually
atmospheric oxygen, that produces oxidized, often gaseous
products, in a mixture termed as smoke.
 Fire is hot because the conversion of the weak double bond
in molecular oxygen to the stronger bonds in the
combustion products carbon dioxide and water releases
energy (418 kJ per 32 g of O2); the bond energies of the
fuel play only a minor role here.

5. CHEMISTRY
REACTIONS
Combustion is two types:–
1.Complete combustion:
CH4 + 2O2 = CO2 + 2H2O
2. Incomplete combustion:
2CH4 + 3O2 = 2CO+ 4H2O
CH4 + O2 = CO + 2H2O

6. FIRE TRIANGLE
To initiate and sustain of fire, three things are need to be
present at the same time:
 OXYGEN
 FUEL
 HEAT

7. TYPES OF FIRE
As far as safety is concerned, there are two
types of fire:
1.Controlled fire:
There is good control on the size, duration,
temperature, smoke and fumes of this type of
fire. They are used in our daily life such as
cooking, heating, Vehicles engines.
2.Uncontrolled fire:
There is no control on the size, duration,
temperature, smoke and fumes of this type of
fire. Temperature can be of 1000º or more. This
type of fire occurs due to accident or due to
criminal act.

8. TYPES OF FIRE
1.Class A fire: “Class A fire" means a fire involving
ordinary combustible materials such as paper, wood,
cloth, and some rubber and plastic materials.
Combustible material burn and ash is left behind.
2.Class B fire: "Class B fire" means a fire involving
flammable or combustible liquids, flammable gases,
greases and similar materials, and some rubber and
plastic materials. Water not to be used as oil is lighter
and will float.
When fires are classified by the type of fuel they burn they are of
5 types:

9. TYPES OF FIRE
3.Class C fire: "Class C fire" means a fire involving
energized electrical equipment where safety to the
employee requires the use of electrically nonconductive
extinguishing media. Electricity itself does not burn but it
provides the ignition t start a fire.
4.Class D fire: "Class D fire" means a fire involving
combustible metals such as magnesium, titanium,
zirconium, sodium, lithium and potassium.
5.Class K fire: Fires involving Combustible vegetable or
animal non-saturated oils or fats in commercial cooking
equipment. Normally occurs in Kitchen.

10. FIRE SPREAD
The heat liberated by the fire also causes the surrounding materials
to warm up. The heat transfer is accomplished by three means,
usually simultaneously:
1.Conduction: Conduction is the transmission of heat through
materials. When there is sufficient heat present, it may be enough to
ignite fuel through other objects. Combustible materials, for
example, are most susceptible to heat transmissions.
2.Convection: Caused by density difference of the hot molecules
compared to the cold ones. Convection normally determines the
general direction of the fire spread. Example: Hot air, Gases expand
and rise.

11. FIRE SPREAD
3.Radiation: This is the transmission of heat by waves travelling
until heat is absorbed by other objects. An example of this would
be a bar heater or open fireplace radiating onto a drying rack or
curtain.

12. THANK
YOU