LESSON 5: FIRE HAZARDS

FIRE HAZARDS

• the occurrence of fire incident serves as one of the most terrifying scenarios for some people

• fire can spread to adjacent proximate areas and become larger

• this phenomenon can occur in a very short time; hence, responders need immediate for every incident

• with its potential for widespread devastation, it is worth looking into its dynamics so people may devise efficient ways of preventing and responding to fire.

ELEMENTS OF THE FIRE TRIANGLE

• a fire cannot be created without its elements/ According to National Fire Protection Association (NFPA 2021)

• remove one of the elements and fire will be extinguished

• A chemical reactions many not be possible if a fuel source or a heat source is misisng

• for this reason the “fire tetrahedron” was established. The representation includes the uninhibited chemical chain reactions

FUEL

• source of burn (reducing agent)

• fire can be reduced

HEAT

• source to make fuel burn

OXYGEN

• most abundant in the air (oxidizing agent)

• fire will increase if more exposed to air

1.IGNITION/INCIPIENT
2.GROWTH
3.FULLY DEVELOPED
4.DECAY

• stages of fire

IGNITION/INCIPIENT

• the easiest to eradicate and serves as the starting point of the fire. This stage would cost the least amount of damage. Nonetheless, fire extinguishers within the area must be quickly used to prevent it from growing into stage 2.

GROWTH

• the fire becomes increasingly difficult to eradicate due to its growing power from the surroundings (oxygen and fuel). Once detected by a fire detection system, it is only a matter of time before it transitions into a flashover

FLASHOVER

• it is the transition point before reaching stage 3, here , al combustible materials contained in an area are now involved in the reactions, thereby reaching or surpassing ignition

FULLY DEVELOPED

• it is the hardest to eradicate. the fire has reached its maximum temperature at this point. Responders must extinguish the fire at this point or else it would cause the maximum amount of damage in an area.

DECAY

• a decrease in the fire’s intensity is a signal of this. This usually occurs when the area’s fuel source is already depleted and there is nothing else to burn. Fire returns to its initial stage as a smolder before ignition.

1.CLASS A
2.CLASS B
3.CLASS C
4.CLASS D
5.CLASS E
6.CLASS F

• summary of classes of fire

CLASS A

• fires involving solid materials such as wood, paper, or textiles

CLASS B

• fires involving flammable liquids such as petrol, diesel, or oils

CLASS C

• fires involving gases

CLASS D

• fires involving metals

CLASS E

• fires involving live electrical apparatus

CLASS F

• fires involving cooking oils such as in deep-fat fryers

1.STARVING
2.COOLING
3.SMOTHERING
4.INHIBITION

• putting out fire

STARVING

• removing or limiting the fuel

COOLING

• removing or reducing the heat

SMOTHERING

• removing or limiting the oxygen

INHIBITION

• INTERRUPTING THE COMBUSTION PROCESS (FIRE SUPPRESIONAL. USE OF EXTINGUISHER)