Objectives
1. Roles of Employees and Employers in
ensuring safety in the workplace
2. Fire Safety
(a) Fire Safety Duties
(b) Basic principle of Fire
(c) Sources of Ignition
(d) Common causes of fire
(e) Classes of fire
(f) Fire Extinguishing Principles
(g) Emergency Procedure during a fire
outbreak
(h) Fire extinction
(a) Fire Safety Roles
The person responsible for Fire Safety must take
appropriate general fire precautions to protect
employees and ensure that the premises is safe.
These general precautions include
(a) Risk assessment and arrangements
(b) Firefighting and fire detection
(c) Emergency routes, exits and emergency
procedures
(d) Training geared towards fire fighting
(e) Having emergency routes, and making sure that
exits are kept free of obstruction
(f) Installation of fire barriers (fire doors, and proofing
of ceilings)
(b) Basic Principle of
Fire
Fire Tetrahedron
Fire cannot take place unless four elements are
present as shown below:
Note:
In order to extinguish fire, one or more elements
from the fire tetrahedron have to be eliminated
(c) Sources of Ignition
Ignition
Refers to the act of starting a fire
Potential sources of ignition might include:
(a) Naked flames – From smoking materials,
and heating appliances e.t.c
(b) External sparks – From grinding metals,
welding tools, impact tools e.t.c
(c)Internal sparking – From faulty electrical
appliances e.t.c
(d) Hot surfaces – From heating appliances,
badly lubricated equipment, hot drive belts e.t.c
(e) Static electricity – Sparking from separation
of materials such as unwinding plastics,
removing synthetic overalls, e.t.c
(d) Common Sources of
Fire
Causes
(i) Poor disposal of smoking materials, such as
cigarette butts
(ii) Poor storage of highly flammable gases and
liquids (for instance near potential sources of
ignition)
(iii) Poor housekeeping that might lead to
accumulation of combustible rubbish
(iv) Overheating of poorly maintained machine
parts
(v) Poor maintenance or improper use/handling of
welding and cutting equipment
(vi) Overloading of electrical equipment
(vii) Damaged cables and improper fuses or failure
of safety devices
(viii) Accumulation of rubbish against electrical
equipment causing overheating
(ix) Overheating of coiled cables used for heavy
current usage
(e) Classes of Fire
Classes
Fire can be classified by the type of fuel involved
(a) CLASS A – These are fires involving
flammable solid materials eg. Fires involving
paper, leather, fabric, wood,
(b) CLASS B – Fires involving flammable liquids
eg. Fires involving petrol
(c) CLASS C – Fires involving flammable gases
such as LPG gas, butane, propane, e.t.c
(d) CLASS D – Fires involving reactive metals
such as Potassium, Sodium, e.t.c
(e) CLASS E – Electric fires
(f) CLASS F – Fires involving high temperature
fats and oils
(f) Emergency
procedures during a
fire outbreak
Emergency procedures are meant to prevent
the spread of fire, and ensure there are no
casualties.
(a) Remove
Remove anyone that is in immediate danger, entangled,
or trapped, only if safe to do so
(b) Alarm
If an automatic smoke/fire detector alarm isn’t running
already, break the nearest fire alarm panel, or should
“Fire! Fire!”
(c) Contain the fire
If it’s safe to do so, and if trained to do so, attempt
putting out the fire. Close doors and windows when it’s
safe to do so, so as to prevent the fire from spreading,
but do NOT lock them
(d) Evacuate
Walk quickly and calmly to the fire assembly point,
and remain there until instructed otherwise
(e) Cutting off electric current
For the purpose of preventing the fire from
escalating by avoiding Electrical Fires
(f) Listen to instructions from emergency
responders
In case there are any emergency responders,
follow their instructions to ensure safe evacuation
(g) Fire extinguishing
principles
Recall
In order to extinguish fire, one or more elements
from the fire tetrahedron have to be eliminated
Principles
With regard to the fire extinction and considering the
fire tetrahedron, there are 4 methods of extinguishing
fire
(a) Smothering – Depriving the fire of air/oxygen
Examples of Extinguishers: CO2, Fire Blanket, Foam
Extinguisher, Wet Chemical
(b) Starving – Depriving the fire of fuel/limiting fuel
supply to the fire
Example: Taking wood out of the fire, or shutting off
electric current in case of a class E fire
(c) Cooling – Reducing the ignition temperature by
taking the heat out of the fire
Examples of Extinguishers: Water, Wet Chemical
(d) Breaking Chemical Reaction – Interrupting the chain
of reaction that sustains the fire
Examples of Extinguishers: Dry powder/chemical,
Halon & Halotron,
(f) Fire extinguishers
and their working
principles
*Water type extinguisher*
*Foam*
*Carbon (IV) Oxide*
*Dry Chemical*
*Wet Chemical*
*Fire Blanket*
EXTINGUISHER DETAILS
Principle: Cooling (reducing the
ignition temperature by taking
1 Water heat out of the fire/ burning
material)
Suitable for: Class A fires
Principle: Smothering (has a
blanketing effect, which limits the
oxygen available and preventing
2 Foam
the mixture of oxygen and the
flammable substance)
Suitable for: Class A & B
EXTINGUISHER DETAILS
Principle: Breaking the chemical
reaction (Interrupting the chain
Dry powder or dry
3 chemical reaction that would sustain the fire)
Suitable for: Class A, B, C, D, & E
Principle: Breaking the chemical
Halon and reaction (Interrupting the chain
4 Halotrons reaction that would sustain the fire
Suitable for: Class A, B, C & E
Principle: Smothering (the fire is
deprived of Oxygen by sealing the
5 Wet Chemical burning liquid and preventing re-
ignition)
Suitable for: Class F (& Class A)
EXTINGUISHER DETAILS
Principle: Smothering (by
displacing Oxygen as CO2 is
6 Carbon (IV) Oxide denser than air and does not
support burning)
Suitable for: Class B & E
Principle: Smothering (by
limiting the supply of
Oxygen reaching the fire,
hence the fire dies off since
combustion requires
7 Fire Blanket Oxygen)
Suitable for: Class B, can
also be used in conjunction
with other fire suppressing
agents
Up Next:
1. Roles of employees and
employers in ensuring
safety
2. Personal Protective
Equipment (PPE’s)
