Fire Extinguishers - rolla.k12.mo.usrolla.k12.mo.us/.../Basic_Portable_Fire_Extinguishers_PowerPoint.pdf · WATER FIRE EXTINGUISHERS ... (Halon 1211 and Halon 1301) ... Manual Pump

To be

effective an

extinguisher:

Must be readily accessible

In working order

Suitable for the hazard

Large enough to control the size fire

Class A: fires

involving

ordinary

combustibles

water, class A dry

or wet chemical,

foam, and mist

A

Class B:fires

involving

flammable

and

combustible

liquids

Extinguished by dry

chemical agents,

foam, clean agents,

or carbon dioxide

B

Class C:fires

involving

energized

electrical

equipment

Extinguished with

nonconductive agents

such as carbon dioxide,

clean agents, mist, and

dry chemical

C

Class D:fire

involving

combustible

metals

Extinguished by Dry Powders Like sodium

chloride which is a material used to cover

the burning metals

Class D is never assigned as

multipurpose extinguisher

D

Class K: fires

that involve oils that are used in commercial cooking applications

These materials have been taken out of the Class B classification

Extinguished with wet chemical

K

Extinguishers must be marked for

which the class of fire they are rated

NFPA 10 recommends

pictographs indicating the fire

class and the types of fires on

which the extinguisher should

not be used

One system

uses colored

shapes with

the class letter

in the shape

Remove

Oxygen

Heat

Fuel

EXINGUISHING PRINCIPLES

EXTINGUISHER RATINGS

Class A and Class B

extinguishers will have a

numerical rating designating

the size fire an untrained

person should be able to

extinguish

Class A extinguishers: rated from 1-A to 40-A -

1-A requires 11/4 gallons of water

Class B extinguishers: rated from 1-B through

640-B

Every 1-B rating corresponds to 1-square-foot

of flammable liquid

No tests are

conducted for

capacity ratings

CLASS C EXTINGUISHERS

Extinguishing

agent is tested

for electrical

conductivity

CLASS D EXTINGUISHERS

No tests are conducted for capacity ratings

Tests are conducted for specific

metals for:

Reactions between the metal and agent

Toxicity of the agent

Toxicity of any fumes produced

Time to allow the fire to self-extinguish versus time to extinguish the fire

For a Class K

rating,

extinguishing

agents must be

able to extinguish

a fire involving

cooking oils with a

surface area of

2.25 square feet

WATER FIRE

EXTINGUISHERSExtinguisher Characteristics:

Size: 2.5 gallons

Discharge distance: 30-40 feet

Duration: 30-60 seconds

Method of expelling agent: pump or pressure

WATER FIRE

EXTINGUISHERS

Agent Characteristics:

Freezing temperature: 32oF

High surface tension

Needs expellant force

Extinguishment principle:

remove heat/cooling

Class A fires only

WATER FIRE

EXTINGUISHERS

Advantages

Limitations

Conducts electricity

Freezes

High surface tension

Reacts with certain chemicals

Absorbs large amounts of

heat

Can be used with specialized

agents

Dry Chemical Extinguishers

Extinguisher Characteristics:

Size: 2.5 to 350 pounds



Method of expelling agent: cartridge/stored pressure

Most Common Extinguisher Made

Sodium bicarbonate:

ordinary

Potassium bicarbonate:

Purple K

Potassium chloride:

Super K

Monammonium phosphate:

multipurpose, Tri-class

Agents:




Uses:

Breaking chain

reaction

Tri-class: smothering

Class A: Tri-class

Class B & C: all types

Dry Chemical ExtinguishersAdvantages

Limitations

Breathing difficulties

Insulating qualities

Corrosive properties

Not flash back resistive

Chemicals not interchangeable

Some not compatible with foam

Nontoxic

Nonconductive

Quick flame knockdown

Clean agent extinguishing agents were

designed to replace halogenated

extinguishing agents (Halon 1211 and Halon 1301)

CLEAN AGENT EXTINGUISHERS

Halon production was

stopped in 1994 due to its

effect on the ozone layer

There is still limited halon

production and much of

the halon in use is

recycled

Extinguish fires through a chemical

process which inhibits combustion

CLEAN AGENT EXTINGUISHERS

Used for Class B and Class C fires

and in areas with sensitive

electronic equipment

High expansion ratio

Needs no expellant

Nonconductive and noncorrosive

Carbon Dioxide Extinguishers

Extinguisher Characteristics

Size: 2.5 to 100 pounds



Method of expelling agent: stored pressure


Agent Characteristics:


smothering

Class B and C fires,

limited effect on Class A

Normally a gas

1.5 times heavier than air

Low temperature

Can be stored as liquid


Advantages

Limitations

Visibility

Noise

Short range

Dissipates rapidly

Displaces oxygen

Nonconductive

Non-reactive

No residue

WET CHEMICAL STORED-PRESSURE EXTINGUISHERS

Specifically

designed to

extinguish fires

involving

unsaturated cooking

oils in deep dryers

Contain a special

potassium-based,

low-pH agent for

class A & K Fires

Foam Fire Extinguisher

Contains: Water, Air, &

Foam Concentrate

Extinguishes A & B Fires

Water Mist Extinguishers

Contains: Deionized Water

Extinguishes with Fine Water

Droplets for A & C Fires

Stored Pressure Which is the most common

Contains an agent in a cylinder with an expellant gas

Discharge handle and may have a gauge

Types of Extinguishers

Manual Pump / Pressure Cartridge


Water CO2

Dry chemical Halon

Clean agents Dry powder

Stored Pressure

1 2 3 4 5

Can you Match the extinguishers below with the Types above?


2 Water 3 CO2

1 Dry chemical 5 Halon

5 Clean agents 4 Dry powder

Stored Pressure

1 2 3 4 5

All obsolete

extinguishers

should be removed

from service and

replaced with

approved

extinguishers

Soda water base with

an acid expellant

Carbon Tetrachloride

was a common

vapor agent used

manual pump &

fire grenade

Extinguisher selection depends on:

Characteristics of the fuels

present

Potential severity of any fire

Extinguisher location

Extinguisher effectiveness

Personnel available and experience

to use the extinguisher

Health and safety concerns

Extinguishers must be

conspicuously located

Installation and placement

Must be readily accessible

Should be located along

normal travel paths,

including exits

Must not be blocked by

storage or equipment

Must be visible or the location

marked conspicuously

Determine if extinguisher is

full and if the pressure gauge

reading in the operable range

Check the locking pin and

tamper seal to determine if it

has been used or tampered with

Check the inspection

tag for the dates of the

previous inspections,

maintenance, and

recharging

Examine for physical damage

Nozzle obstructions

Corrosion

Mechanical damage

Hose condition

Horns for cracks and obstructions

Hydrostatic testing

EXTINGUISHER OPERATION

Pull pin

Aim nozzle

Squeeze handle

Sweep nozzle

Check extinguisher before approaching

EXTINGUISHER SAFETY

Approach upwind

Don’t enter burn area

Don’t turn back on fire

Review

1. Know the 5 classes of fires and which fire

extinguishers are rated for each class?

2. What are the principals of how to extinguish a

fire?

3. How are all fire extinguishers rated?

4. List the different types of fire extinguishers?

5. What is the acronym for using a fire extinguisher

and what does it stand for?

1. Know the 5 classes of fires and which fire extinguishers are rated for each class?

Class A – Ordinary / Water, Wet or Dry Chemicals, Foam, or Mist

Class B – Flammable Liquids / Dry Chemicals, Foam, Clean Agents, or CO2

Class C – Energized Electric / Dry Chemical, Clean Agents, Mist or CO2

Class D – Flammable Metals / Dry Powders

Class K – Cooking Oil / Wet Chemicals

2. What are the principals of how to extinguish a fire?

By Removing any side of the fire tetrahedron; Remove Heat (Cooling), Oxygen

(Smothering), Fuel (Starving) or by Inhibiting the Chemical Reaction.

3. How are fire extinguishers rated?

A - 1 ¼ Gallons of water B - Per Square Feet C - If it will Conduct

Electricity D - Metal Specific K-Cooking Oils

4. List the different types of fire extinguishers?

Water, Dry Chemical (The Most Common Extinguisher), Clean Agents (Halon

Type), CO2 (Carbon Dioxide), Wet Chemical, Foam, and Mist

5. What is the acronym for using a fire extinguisher and what does it stand for?

PASS P-Pull the Pin A-Aim the Extinguisher S-Squeeze the Trigger S- Sweep

at the base of the fire

Fire Extinguishers - rolla.k12.mo.usrolla.k12.mo.us/.../Basic_Portable_Fire_Extinguishers_PowerPoint.pdf · WATER FIRE EXTINGUISHERS ... (Halon 1211 and Halon 1301) ... Manual Pump

Documents