To be effective an extinguisher: Must be readily accessible In working order Suitable for the hazard Large enough to control the size fire Must be readily accessible In working order Suitable for the hazard Large enough to control the size fire

Remove GOxygen GHeat GFuel Remove GOxygen GHeat GFuel EXINGUISHING PRINCIPLES Chemical Inhibition

WATER FIRE EXTINGUISHERS Extinguisher Characteristics: Size: 2.5 gallons Discharge distance: feet Duration: seconds Method of expelling agent: pump or pressure

WATER FIRE EXTINGUISHERS Agent Characteristics: X Freezing temperature: 32 o F X High surface tension X Needs expellant force Extinguishment principle: remove heat/cooling Class A fires only

WATER FIRE EXTINGUISHERS Advantages Limitations X Conducts electricity X Freezes X High surface tension X Reacts with certain chemicals X Absorbs large amounts of heat X Can be used with specialized agents

Dry Chemical Extinguishers Extinguisher Characteristics: Size: 2.5 to 350 pounds Discharge distance: 5-20 feet Duration: 8-25 seconds Method of expelling agent: cartridge/stored pressure

Sodium bicarbonate: ordinary Potassium bicarbonate: Purple K Potassium chloride: Super K Monammonium phosphate: multipurpose, Tri-class Sodium bicarbonate: ordinary Potassium bicarbonate: Purple K Potassium chloride: Super K Monammonium phosphate: multipurpose, Tri-class Agents: Dry Chemical Extinguishers

Extinguishment principle: Uses: IBreaking chain reaction ITri-class: smothering IBreaking chain reaction ITri-class: smothering L Class A: Tri-class L Class B & C: all types L Class A: Tri-class L Class B & C: all types

Dry Chemical Extinguishers Advantages Limitations L Breathing difficulties L Insulating qualities L Corrosive properties L Not flash back resistive L Chemicals not interchangeable L Some not compatible with foam L Breathing difficulties L Insulating qualities L Corrosive properties L Not flash back resistive L Chemicals not interchangeable L Some not compatible with foam I Nontoxic I Nonconductive I Quick flame knockdown I Nontoxic I Nonconductive I Quick flame knockdown

Carbon Dioxide Extinguishers Extinguisher Characteristics: Size: 2.5 to 100 pounds Discharge distance: 3-8 feet Duration: 8-30 seconds Method of expelling agent: stored pressure

Carbon Dioxide Extinguishers Agent Characteristics: Extinguishment principle: 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

Carbon Dioxide Extinguishers Advantages Limitations Visibility Noise Short range Dissipates rapidly Displaces oxygen Nonconductive Non-reactive No residue

Halon: production was stopped in 1994 Halogenated Hydrocarbons Halon replacement agents – “clean agents” FM-110FM-200 InergenHaltron May require up to 20 times as much as halon to provide an equal extinguishing capacity

Halogenated Hydrocarbons Extinguisher Characteristics: Size: 2.5 to 100 pounds Discharge distance: 3-8 feet Duration: 8-30 seconds Method of expelling agent: stored pressure

Halogenated Hydrocarbons Extinguishment principle: a chemical process that inhibits combustion Class B and C fires: used in areas with sensitive electronic equipment

Halogenated Hydrocarbons Advantages High-expansion ratio Needs no expellant Nonconductive Non-corrosive No residue Halon can be toxic and creates other toxic gases under fire conditions

FOAM EXTINGUISHERS Extinguisher Characteristics: Size: 2.5 gallons Discharge distance: feet Duration: 50 seconds Method of expelling agent: stored pressure

FOAM EXTINGUISHERS Agent Characteristics: X Gas-filled bubbles X Floats on flammable liquids X Can be proportioned at various concentrations Extinguishment principle: smothering, some cooling Class A and B fires

FOAM EXTINGUISHERS Advantages Limitations X Not compatible with some other agents X Freezes X Discharge distance X Conducts electricity X Nontoxic X Flow capabilities

Dry Powder Extinguishers Extinguisher Characteristics: Size: 30 to 350 pounds Discharge distance: feet Duration: seconds Method of expelling agent: cartridge/stored pressure, shovel

Dry Powder Extinguishers Designed for Class D fires Agent Characteristics: Fine powder Needs expellant force No single agent is effective on all types of combustible metals

Dry Powder Extinguishers No single agent is effective on all combustible metals Limitations Can become packed Cannot interchange chemicals Expensive L NA-X: for sodium and potassium L MET-L-X: for sodium, potassium and magnesium L LITH-X: for sodium, lithium, zirconium, and magnesium

Contains an agent in a cylinder with an expellant gas Discharge handle and a gauge Types of Extinguishers Stored Pressure

Types of Extinguishers WaterFoam Dry chemicalHalon Clean agentsDry powder CO 2 Stored Pressure

Cartridge Operated Contain the explant gas in a separate cartridge from the agent Does not have a pressure gauge Types of Extinguishers

EXTINGUISHER OPERATION P ull pin A im nozzle S queeze handle S weep nozzle P ull pin A im nozzle S queeze handle S weep nozzle

Check extinguisher before approaching EXTINGUISHER SAFETY Approach upwind Don’t enter burn area Don’t turn back on fire