FIRE PREVENTION/PROTECTION
Fire protection entails mitigating potentially hazardous effects of fire through good practices and fire education.
Goals
The essence of fire prevention is to:
(a). protect life and property from destructive fires
(b). prevent work interruption,
(c). ensure work continuity
(d). mitigate fire inception.
Fire Suppression responders Priorities
The first priority is to:-
(a).save lives beginning with self.
(b). reduce potential damages
(c). save property from destructive fires.
Relationship with Insurance
(i). Accidental fire connects a fire break-out not intentionally incepted but through external factor.
(ii). Arson on the contrary, is intentional inception of fire to cause damage.
In case of fire break-out
(a). people should exit the building
(b). gather in fire safety point.
HUMAN BEHAVIOR
Most people brush-off fire outbreak due to insurance covers and lack of stringent law and policies.
Reactions to Fire
They depend on personality of an individual and previous experience, perceived threat, the physical features of the structure ablaze, and behaviors of others present. Dangerous reactions include: -
(a). clustering at one point within a blazing structure.
(b). re-entry to the structure.
(c). Anxiety and panic
(d). fighting the fire aimlessly.
Note: While female often send a sound alarm and evacuate, men on the other hand tend to fight the fire.
Sources of fire
Fire can result from any of the following:-
(a) Friction.
(b) Fuel.
(c) Fire frame.
(d) And electric fault.
TYPES OF ENERGY
There are four main types:–
(a). electrical
(b). mechanical
(c). chemical
(d). nuclear and solar heat energy.
CLASSES OF FIRE
They are summed up in the following diagram:
PHASES OF A FIRE
There are three main:-
(a). Incipient (temperature above 380C).
(b). steady-state (7000C) with high oxygen supply and fire accumulates in upper area of the structure with simultaneous ignition of all combustibles.
(c). lastly is hot smoldering in which oxygen supply is very low but reintroduction reignites the fire.
Heat Transfer
Can be transferred either through:-
(a) Conduction – horizontal and vertical.
(b) convection via gas or liquid,
(c) radiation,
(d) Encounter with flame directly
PROTECTIVE CLOTHING
The five main components include helmets, jackets with thermal liner, pants with suspender, steelboots that can protect against hot heat, and gloves. Noteworthy, a moist component is a good shield – but none can protect against radioactivity, excessive heat, and air supply.
SCBA System
The SCBA system can either be:-
(a). closed circuit
(b). open circuit.
The efficiency of SCBA depending on:-
(a). One’s breathing control rate.
(b). mechanical conditions.
(c). one’s expertise and skills
(d). Person’s physical ability.
The SCBA duration efficiency is also influenced by other factors such as:-
(a). oxygen supply – low.
(b). thickness of smoke
(c). toxicity of burning particles.
(d). respiratory condition,
(e). stress and physical ability.
Important steps here are reaching the air cylinder and face masking against the fire with intervals of safe-breathing. It is advisable to work closely with a partner.
SCBA components
SCBA consists of four main components:-
(a) The tank with compressed air
(b) harness assemble,
(c) Access to regulator systems
(d) masks against the fire.
PRODUCTS OF COMBUSTION
Products that can easily generate into fire include:-
(a). heat
(b). flame
(c). combustible gas
(d). and smoke.
Anything that poses threat to life safety or environment is hazardous.
Protection against fire contact
One can protect from contact by:-
(a). wearing uniform
(b). mask for eyes and face.
(c). Putting on breathing apparatus among others.
Extinguishers
They are classified into four classes:-
A - Ordinary combustibles
B - Flammable liquids
C - Live electrical fires
D - Combustible metals.
Materials used in fire extinguishing
Extinguishers can be:-
(a). water-based
(b). carbon-dioxide,
(c).dry powder
(d). halogenated or foam-based.
Water is mainly used as primary extinguishing agent because:-
a) Its availability
b) Affordability
c) it’s quite effective
d) can easily be stored and
e) Its portability over long distances.
However, it has limitations in that:
a) it is relatively heavier compared to compressed gas
b) Iit can over-accumulate in the buildings increasing structure collapse due to overweight
c) Cannot be used on Class C fires unless the electrical source is eliminated
d) Violent reaction when water is applied to combustible metal fire.
Selection of Portable Fire Extinguisher
It depends on:-
a) the class of the fire
b) effectiveness of the extinguisher
c) severity and the damage to mitigate
d) Environmental conditions – weather, skills, ease of use.
Operation and detection of Fires
Operating extinguishers is quite simple; it entails:-
a) Pulling the pin
b) Aiming at the flames
c) And squeezing the handle while sweeping back and forth.
The apparatus can be maintained in-house or contracted and regular inspections are recommended. Fire outbreaks can be detected by systems that send audible alarm.
Installation of fire extinguishers
Their installation is guided by:
a) The nature of combustion expected
b) effects of delay
c) Value attached to the property.
Fire detection system
The signals may be fire-alarm, supervisory alert or trouble indicator.
Types of fire detector
These includes: -
a) Heat
b) Smoke
c) Other detectors – pressure, flame, gas.
The protective signaling system may be centrally placed, remote-based, local or proprietary.
WATER SYSTEM
Water can be obtained from wells and reservoirs, log pipes, bucket brigade or an aqueduct.
Component of modern water supply system:
Water is transferred by:
(a). direct pumping
(b). gravity
(c) Combination of both.
a) Butterfly
b) Post-indicator
c) gate valve
d) Outside screw and yoke valves.
The hydrants should be inspected regularly to detect an obstruction or dysfunction.
SPRINKLER SYSTEMS
A sample fire-safety sprinkler has the following features
Water releasing mechanisms include via:-
a) Fusible link
b) Glass bulb
c) Chemical pellet or quick response type.
The sprinkler designs are mainly pendent, sidewall or upright. When using the sprinklers it’s prudent to evaluate advantages and limitations of using foams, water, gas or dry chemical.
Building Designs
Building design influences decisions on fire protection. Buildings can be designed to be:
a) Fire resistance – with precast concrete slabs.
b) Non-combustible
c) ordinary constructions which may not be fire resistant but non-combustible,
d) And heavy temper or mill which is good in event of fire break out – it takes time to burn.
Combustible Furnishing/finishing
In case of building collapse, it’s is prudent to protect yet to burn property (solvage) and overhole even if the instructions for firefighting are cancelled.
Training – not all people are trained, only a few – it’s less costly. They are taught the SCBA procedures. One needs a fire department to be able to offer such training.
