1 Basic Principles of:. Basic Objectives 1.1 The firefighter shall define heat and fire. 1.2 The firefighter shall define the fire triangle and tetrahedron

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Basic Principles of:Basic Principles of:

Basic ObjectivesBasic Objectives

1.1 The firefighter shall define heat and fire. 1.2 The firefighter shall define the fire triangle

and tetrahedron. 1.3 The firefighter shall identify two (2) chemical,

mechanical, and electrical energy heat sources. 1.4 The firefighter shall define the following

stages of fire:a) Incipientb) Flame spreadc) Hot smolderingd) Flashovere) Steady statef) Clear or free burningg) Back draft explosion

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1.5 The firefighter shall define the three (3) methods of heat transfer.

1.6 The firefighter shall define the three (3) physical states of matter in which fuels are commonly found.

1.7 The firefighter shall define the hazard of finely divided fuels as they relate to the combustion process.

1.8 The firefighter shall define:a) Flash pointb) Fire pointc) Ignition temperatured) Upper and lower explosive limits

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1.9 The firefighter shall define concentrations of oxygen in the air as it affects combustion.

1.10 The firefighter shall identify three products of combustion commonly found in structural fires which create a life hazard.

1.11 The firefighter shall identify characteristics of water as it relates to its fire extinguishing potential.

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The firefighter shall define heat and fire:

Heat - a form of energy characterized by vibration of molecules and capable of initiating and supporting chemical changes and changes of state.

Fire - a rapid oxidation process with the evolution of light and heat in varying intensities.

The firefighter shall define the fire triangle and tetrahedron::

Fire triangle - Fuel, heat and an oxidizing agent (air) are components which are necessary to sustain combustion

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Fires can be prevented or suppressed by controlling or removing one or more of the sides of the tetrahedron.

Fire tetrahedron –The combustion reaction can be characterized by four components: The fuel the oxidizing agent, the heat and the uninhibited chemical chain reaction. These four components have been classically symbolized by a four-sided solid geometric form called a tetrahedron.

Fuel

Heat

Oxygen or Oxidizing agent

Uninhibited ChemicalChain Reaction

This is theFire Triangle

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Fire is a chemical process known as combustion. It is frequently described as the rapid oxidation of combustible material accompanied by a release of energy in the of heat and light. There are four products of combustion:

• Heat -

Most responsible for the spread of fire.Direct cause of burns, dehydration, heat exhaustion, and respiratory injuries.

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• Heat - Most responsible for the spread of fire.Direct cause of burns, dehydration, heat exhaustion, and respiratory injuries.

• Light -

Flame is the visible, luminous body of a burning gas. When burning gas is mixed with the proper amounts of oxygen, the flame becomes hotter and less luminous.

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• Heat - Most responsible for the spread of fire. Direct cause of burns, dehydration, heat exhaustion, and respiratory injuries.

• Light - Flame is the visible, luminous body of a burning gas. When burning gas is mixed with the proper amounts of oxygen, the flame becomes hotter and less luminous.

• Smoke -

The smoke encountered at most fires consists of a mixture of oxygen, nitrogen, carbon dioxide, carbon monoxide, finely divided carbon particles (soot), and miscellaneous assortment of products that have been released from the material involved.Liquid fuels, oil, tar, paint, rubber, and sulfur generally give off dense, black smoke.Some materials burn with virtually no smoke such as alcohol and charcoal.

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Fire is a chemical process known as combustion. It is frequently described as the rapid oxidation of combustible material accompanied by a release of energy in the form of heat and light. There are four products of combustion:

• Heat • Light • Smoke

• Gasses -

Gasses are produced by the pyrolysis of the material being burned. They are what’s really burning during a fire. Some fire gases may not completely burn and can produce a lethal atmosphere.Carbon monoxide is produced by the incomplete combustion of a burning material.Hydrogen chloride combines with the moisture in the lungs to produce hydrochloric acid. It is a gaseous by-product of the burning of many plastics including polyvinyl chloride (PVC).Hydrogen cyanide can be produced in the burning of wool, nylon, polyurethane foam, rubber, and paper. It is a chemical asphyxiant and interferes with the ability of the body tissues to use oxygen.Nitrogen oxides are produced by the decomposition of pyroxylin plastics, plastics frequently used to make drafting tools, rulers, etc. Forms nitric acid in the lungs and can lead to fatal pulmonary edema. May not be apparent for several house after exposure.Phosgene is produced from the burning of Freon® and other refrigerants. It is a strong lung irritant and may not be evident for several hours after exposure. It forms hydrochloric acid in the lungs.

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The firefighter shall define the following stages of fire:

1. Incipient: Is the earliest phase of a fire beginning with the actual ignition.

The fire is limited to the original materials of ignition.

The oxygen content in the air has not been significantly reduced, and the fire is producing water vapor, carbon dioxide, perhaps a small quantity of sulfur dioxide, carbon monoxide, and other gases.

Although the flame temperature may be well above 1,000° F., the temperature in the room may only be slightly increased.

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1. Incipient:

2. Flame Spread: the movement of flame away from an ignition source and intoadjacent areas and materials.

Is the earliest phase of a fire beginning with the actual ignition.

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1. Incipient:

2. Flame Spread:

3. Hot Smoldering: combustion without flame, usually with incandescenceand smoke.


During the hot smoldering phase of a fire, flames may cease to exist if the area of confinement is sufficiently airtight. Burning is reduced to glowing embers.

As flames die down, the room is completely filled with dense smoke and gases. Air pressure may build to the point that smoke and gases are forced through small cracks.

Total room temperatures in excess of 1,000° F. are possible. The intense heat will have liberated most of the flammable gases, such as methane, from combustible material in the room.

A backdraft hazard is produced. If no air is introduced, the fire will burn out leaving totally incinerated contents.

the movement of flame away from an ignition source and intoadjacent areas and materials.

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1. Incipient:

2. Flame Spread:

3. Hot Smoldering: combustion without flame, usually with incandescenceand smoke.

4. Flashover:

A transition phase in the development of a contained fire in which surfaces exposed to thermal radiation reach ignition temperaturemore or less simultaneously and fire spreads rapidly throughout the space.


The cause is attributed to the buildup of heat from the fire itself. As the fire continues to burn, all the contents of the room are gradually heated to their ignition temperatures. When they reach their ignition point, simultaneous ignition occurs, and the area becomes fully involved in fire.

the movement of flame away from an ignition source and intoadjacent areas and materials.

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6. Clear and Free Burning:

The phase where sufficient oxygen and fuel are availablefor fire growth and open burning to a point where totalinvolvement is possible.

Extinguishment of the fire at this stage requires application of water or otheragent to the seat of the fire. Water can be applied sparingly at the ceiling level to cool the thermal layer and reduce flashover potential.

Too much water will produce excess steam, which can injure persons and drive firefighters from the building.

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6. Clear and Free Burning:

The phase where sufficient oxygen and fuel are availablefor fire growth and open burning to a point where totalinvolvement is possible.

7. Back Draft Explosion:

An explosion resulting from the sudden introduction of air (oxygen) into a confined space containing oxygendeficient superheated products of incomplete combustion.

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The firefighter shall identify two (2) chemical, mechanical and electrical energy heat sources.

Chemical: 1. Heat of combustion (burning) - is the amount of heat generated by combustion (oxidation reaction). The amount of heat generated by burning materials will vary dependingon the material. Some materials are said to burn “hotter” than others do.

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Chemical: 1.

2.

Heat of combustionHeat of combustion

Spontaneous heating - is the heating of organic substancewithout the addition of external heat. It occurs most frequently where sufficient air is not present and insulation prevents the dissipation of heat. This heat is produced by low-grade chemical breakdown process. An example would be oil-soaked rags that are rolled into a ball and thrown into a corner. If there is not enough ventilation to allow the heat produced to drift off, eventually the heatwill become sufficient to cause ignition of the rags.

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Chemical: 1.

2.

Mechanical: 1.


Spontaneous heatingSpontaneous heating

Heat of friction - is created by the movement of twosurfaces against each other. This movement results in heat and/or sparks being generated.

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Chemical: 1.

2.

Mechanical: 1.

2.



Heat of frictionHeat of friction

Heat of compression - is generated when a gas is compressed. Diesel engines ignite fuel vapor with out a spark plug by the use of this principle. A gas cylinder such as a SCUBA bottle feels warm to the touch afterfilled with air.

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Chemical: 1.

2.

Mechanical: 1.

2.

Electrical: 1.




Heat of compressionHeat of compression

Resistance heating - refers to the heat generated bypassing an electrical current through a conductor suchas a wire or an appliance. Resistance heating is increasedif the wire is not large enough in diameter for the amountof current carried. Fires can be caused when a standard household extension cord is overloaded with to manyappliances plugged into it. Resistance heating can also beincreased if the conductor is tightly wound or coiled.

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Chemical: 1.

2.

Mechanical: 1.

2.

Electrical: 1.





Resistance heatingResistance heating

2. Heat from arcing - is a type of electrical heating thatoccurs when the current flow is interrupted. Interruptionmay be from an open switch of a loose connection. Arctemperatures are extremely high and may even melt theconductor. An example used in industrial applicationsis a welder. The welding rod (conductor) melts away as the metals melt and are joined together.

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Chemical: 1.

2.

Mechanical: 1.

2.

Electrical: 1.





Resistance heatingResistance heating

2. Heat from arcingHeat from arcing

Another heat source which can be listed is:

Nuclear heat source: Is generated when atoms are either split apart (fission)or combined (fusion). In a controlled setting, fission is used to heat water to drive steam turbines and produceelectricity. Currently fusion cannot be controlled and has no commercial use.

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Several of the natural laws of physics are involved in the transmission of heat. The “Law of Heat Flow” specifies that heat tends to flow from a hot substance to a cold substance. The colder of the two bodies in contact will absorb heat until both objects are the same temperature. Heat can travel through a building by one or more methods.

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“Heat transfer to another body or within a body by direct heat”

Conduction is the form of heat transfer that takes place within solids when one portion of an object is heated. Energy is transferred from the heated area to the unheated area at a rate dependent on the difference in temperature and the physical properties of the material.

Definition:

Heat may be conducted from one body to another by direct contact or by an intervening heat-conducting medium.

Liquids and gases are poor conductors of heat because of the movement of their molecules, and air is a relatively poor conductor.

-- This is why double walls and storm windows that contain an air space provide additional insulation from outside temperatures.

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Definition:

“Heat Transfer by circulation within a medium such as a gas or a liquid”

Convection is the transfer of heat energy by the movement of heated liquids or gases from the source of heat to a cooler part of the environment. Heat is transferred by convection to a solid when hot gases pass over cooler surfaces. The rate of heat transfer to the solid is a function of the temperature difference, the surface area exposed to the hot gas, and the velocity of the hot gas. The higher the velocity of the gas, the greater the rate of convective transfer.

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Definition:

“Heat transfer by way of electromagnetic energy”

Radiation is the transfer of heat energy from a hot surface to a cooler surfaceby electromagnetic waves without an intervening medium. For example, the heat energy from the sun is radiated to earth through the vacuum of space.Radiant energy can be transferred only by line-of-sight and will be reduced orblocked by intervening materials. Intervening materials do not necessarily block all radiant heat. The rate of heat transfer is also strongly affected by thedistance between the radiator and the target. As the distance increases, the amount of energy falling on a unit of area falls off in a manner that is relatedto both the size of the radiating source and the distance to the target.

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The firefighter shall define the three (3) physical states of matter in which fuels are commonly found.

1. Solids

2. Liquids

3. Gases

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Fuel may exist in any of the physical states of matter -- gas, liquid or solid. A solid is a substance whose molecules, at ambient temperature, are held tightly in a fixed three-dimensional relationship to one another by molecular forces. A solid has fixed volume and shape. A liquid at ambient temperature has molecules held less tightly. A liquid has a fixed volume but not a fixed three-dimensional shape. A gas at ambient temperature has only weak bonds between it molecules and will expand to fill any available volume.

The state of fuel is directly related to temperature and pressure and can change as conditions vary. At very high temperatures, solids may liquefy, and both solids and liquids will give off vapors. At very high pressure, gases may become liquefied.

In order for solid and liquid materials to burn, these materials must be heated sufficiently to produce vapors. It is the vapors that actually burn. The lowest temperature at which a solid or liquid material produces sufficient vapors to burn under laboratory conditions is known asthe flash point. A few degrees above the flash point is the flame point, the temperature at which the fuel will continue to produce sufficient vapors to sustain a continuous flame. Thetemperature at which the vapors will ignite is the ignition temperature, also called the autoignition temperature.

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Solid fuels have a definite shape and size that significantly affect the ignitability of the fuel.

The primary consideration is the surface-to-mass ratio as this ratio of surface area to mass increases; the fuel particles become more finely divided (sawdust as opposed to logs).

As the surface area increases, heat transfer is easier and the material heats more rapidly, thus speeding pyrolysis.

Fire spread is more rapid in a vertical direction than horizontally

Examples: Wood

Coal

Flammable metals

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Liquid fuels have physical properties that increase the difficulty of extinguishment and the hazard to personnel

A liquid will assume the shape of its container. When spilled, a liquid will assume the flat shape of the ground, and it will flow and accumulate in low spaces.

Examples: Gasoline

Crude Oil

Alcohol

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Gases can be flammable if the molecules are combined with the proper amount of air to support combustion.

The upper and lower flammable limits define the zone where a gas can burn. Some gases like acetylene have such a low flammability limit that they can burn in the presence of only a small amount of air.

Gases that are heavier than air, such as propane and ethane, will sink and accumulate in low spaces.

Extra caution is needed to recognize hazardous area when working with gases.

Examples: MethaneHydrogen

Butane

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Fuel may be found in the three states of matter:

1. Solid

2. Liquid

3. Gas

The initiation of combustion of a liquid or solid fuel requires their conversion into a gaseous state by heating. Fuel gasses are evolved from solid fuels by pyrolysis.

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Specific gravity is the measurement of the density of liquids in relation to water. Liquids with a specific gravity of less than one are lighter than water. Those with a specific gravity greater than one are heavier than water. Any liquid with a specific gravity of one will mix evenly with water.

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Vapor density is the density of gas or vapor in relation to air. If a gas has a vapor density lessthan one (that of air), it will rise and dissipateinto open air. Gases with a vapor density greaterthan one tend to settle, hug the ground, and travelas directed by terrain and wind. All hydrocarbonfuels with the exception of methane, have a vapordensity greater than one, and will hug the ground,flow into low-lying areas where sources of ignitionmay exist.

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Fuel to Mass Ratio is the ratio for the surface areaof the fuel to the mass of the fuel. As this ratio increases, the fuel particles become smaller and finely divided (coal dust as opposed to lumps of coal) and the ignitability increases tremendously.As the surface area increases, heat transfer is easier and the material heats more rapidly, thusspeeding pyrolysis.

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When a material burns, it undergoes a chemical change.None of the elements make up the material are destroyedin the process, but all of the material is transformed intoanother form or state.

--When a piece of paper burns the gases and moisture contained within the paper are liberated. The remaining solids take on the appearance of carbonized, charred flakes.

--It was once thought that the weight of the by-products of combustion would exactly equal the original weight of the fuel. It is now known that a tiny amount of the fuel is indeed converted into energy, so the by-products weigh slightly less than the fuel did.

The firefighter shall define the hazard of finely The firefighter shall define the hazard of finely divided fuels as they relate to the combustion divided fuels as they relate to the combustion process:process:

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Smoke most often is defined as the airborne solid and liquidparticulates and fire gases evolved when a material undergoespyrolysis or combustion. The fire gases have received the most attention, while knowledge of the effects of inhalation of particulates and aerosols from smoke is still quite limited.

Carbon monoxide (CO) is not the most toxic of fire gases, but it is themost abundant and, therefore, is always the major threat in most fire atmospheres. The toxicity of CO is primarily due to its affinity for the hemoglobin in the blood, decreasing the capability of the bloodto transport oxygen throughout the body.


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Hydrogen cyanide (HCN) is produced from the burning of materials that contain nitrogen. Natural and synthetic materials such as wool,silk, nylon, polyurethanes, and urea-containing resins are included.HCN is a rapidly acting toxicant which is 20 times more toxic thanCO. HCN inhibits the use of oxygen inside the cells.

Carbon dioxide (CO) is usually evolved in large quantities fromfires. CO causes increased rate and depth of respiration, causing thebody to breath in more of the other fire toxicants and irritants. At a10% concentration of CO, the breathing speed and depth may beincreased up to 8 to 10 times normal.


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Hydrogen chloride (HCI) is formed from the combustion of chlorine-containing materials, the most notable of which is polyvinyl chloride (PVC). It is a potent sensory and pulmonary irritant. 75 PPM can cause eye irritation. Exposures of over 700 PPM for more than 30 minutes are highly dangerous. HCI cancombine with moisture in the lungs to form hydrochloric acid.

Nitrogen dioxide (NO) and nitric oxide (NO) comprise a mixtureusually referred to as NO×. These nitrogen oxides result from the oxidation of nitrogen-containing materials, with HCN also being a source of NO× when it is burned at high temperatures. NO× has alethality comparable to HCN. It is most lethal in the lungs with death coming up to a day after a fatal exposure.

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THE FIREFIGHTER SHALL DEFINE:THE FIREFIGHTER SHALL DEFINE:

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FLASH POINT -

A solid or a liquid, if heated sufficiently, will give off a vapor capable of ignition. The temperature at which the application of flame will cause this vapor to ignite is termed the FLASH POINT. The flash point is recorded as the temperature at which ignition occurs to the vapor given off by the solid or liquid. It is the minimum temperature which will ignite the vapor. It is not the temperaturewhich will sustain burning; that is the fire point.

FIRE POINT -

The FIRE POINT is defined as the lowest temperature at whichvapors are burning at the same rate that they are generated. At the fire point, the temperature is high enough to support continuouscombustion. It will burn 10º to 50º F above the flash point.


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IGNITION TEMPERATURE -

Ignition or auto-ignition temperature is that temperature to which thesubstance must be raised for vapors to ignite spontaneously withoutthe presence of an independent source of heat. The ignition temperatureis a function of degree of molecular activity of the vapor and is influencedby the rate of air flow, rate of heating, size and shape of the material,as well as the source of oxygen available for the chemical process to beginand become self sustaining.

LOWER UPPER AND EXPLOSIVE LIMITS -

Flammable Limits: The upper or lower concentration limits at a specifiedtemperature and pressure of flammable gas or a vapor of an ignitable liquidand air, expressed as percentage of fuel by volume that can be ignited.

Flammable Range: Concentration range of a flammable gas or vapor of a flammable liquid in air that can be ignited.


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UPPER AND LOWER EXPLOSIVE LIMITS (cont.)-

Explosive Limits: Most of us are familiar with the phenomenon of being unable to start a car because the carburetor was flooded, resulting in toorich a mixture (of gasoline and air), or the carburetor being out of adjustment, resulting in to lean a mixture.

This phenomenon indicates that the carburetor was supplying fuel to the car either above or below the flammable or explosive limits of the gas.Practically all flammable gases or liquids which can be vaporized have limits beyond which the mixture will not burn. These are called the explosive or flammable limits. The range between the upper and lowerlimits is called the explosive or flammable range of the substance.

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While not a true gas, occurs when the fire consumes available oxygen in an area. Oxygen concentrations less than 17% can cause impairment of motor skills. 14% to 10% may cause fatigue and faulty judgement. 10% to 6% will cause unconsciousness and impending death.

In most fire situations, the oxidizing agent is the oxygen in the earth’s atmosphere. Fires can occur in the absence of atmospheric oxygen, when fuels are mixed with chemical oxidizers. Many chemical oxidizers contain readily released oxygen. Ammonium nitrate fertilizer, potassium nitrate and hydrogen peroxide are examples.

The Firefighter shall define concentrations of oxygen in air as it affects combustion

Air contains approximately 21% oxygen. With out an air supply, insufficientoxygen often results during combustion. Flaming combustion usually ceaseswhen the available oxygen is less that 16 %.

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The Firefighter shall identify three The Firefighter shall identify three products of combustion commonly products of combustion commonly found in structural fire which found in structural fire which create a fire hazard.create a fire hazard.

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Four categories of combustion byproducts are produced as the result of combustion:

1. Gases

Fire gases produced in most fires depend on certain variables, including the chemicalmakeup of the burning materials, the available oxygen during burning, and/orthe temperature of the fire and the fire area.

The toxicity of these gases is determined by variables such as the concentration (percent) of gas in the air, the length of exposure, and the physical condition ofthe victim.

The toxic effects on personnel are greater during the fire because of increased respiration by the victim from exertion, heat and excess carbon dioxide. Whatordinarily appear to be harmless amounts of toxic by products may becomedangerous during the fire.


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1. Gases

2. Flame

Flame results from the burning of most materials in an oxygen-rich atmosphere.This produces luminosity (flame). Therefore, flame is considered to be a “byproduct” of combustion.


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1. Gases

2. Flame

Heat is commonly defined in terms of intensity of heating rate (Btu/sec or kilowatts)or as the total heat energy received over time (Btu). In a fire, heat produces fuel vapors, cause ignition, and promotes fire growth and flame spread by maintaining a continuous cycle of fuel production and ignition. The presence of moisture in heated air increases the danger and the damage.

3. Heat

The Firefighter shall identify three The Firefighter shall identify three products of combustion commonly products of combustion commonly found in structural fire which create a found in structural fire which create a fire hazard.fire hazard.

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1. Gases

2. Flame

3. Heat

4. Smoke

Smoke consists of very fine solid particles and condensed vapor. Gases that areproduced by the heating of combustible materials are contained in flammable tardroplets and carried upward within the thermal column. Very little smoke is produced during complete combustion. As combustion diminishes, smoke densityincreases.

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The Firefighter shall identify The Firefighter shall identify characteristics of water as it relates to its characteristics of water as it relates to its fire extinguishing potential.fire extinguishing potential.

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Water has the ability to extinguish fire inseveral ways. The primary way is by cooling.It may also be used to smother a fire, excludingoxygen.

Water exits in a liquid state between 32º F. and 212º F. Below 32º F. it turns to ice and above 212º F. it turns to steam. When steam cools and converts back to water it is know as condensed steam. It ranges from 60 lb/ft³ at freezing and 60 lb/ft³ close to boiling. Each pound of water requires approximately 970 Btu’s of additional heat to completely turn into steam. When water is converted to steam, it expands 1700 times it original volume.

The Firefighter shall identify characteristics of The Firefighter shall identify characteristics of water as it relates to its fire extinguishing water as it relates to its fire extinguishing potential.potential.

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The large heat of vaporization is another reason for the effectiveness of water as an extinguishing agent. The heat absorbed by the water is subtracted from the burning system so it cannot be used for vaporizing more liquid or pyrolyzing more solid fuel. A relatively large amount of heat is required to change water into steam. The greater the surface area of the water absorbed, the more rapidly heat will be absorbed. Disadvantages of water include it weight ( 8+ pounds per gallon), it is conductor of electricity, and use of water can spread light than water fuel fires. The conversion of water into steam accompanied by rapid expansion can burn firefighters or trapped victims.

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Basic Fire Behavior End Note:Basic Fire Behavior End Note:

Personal Size-UPAlways make a

continuous mental evaluation of your immediate environment, facts, and probabilities to come home safe, and Good Luck!!!!

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Intermediate Principles Intermediate Principles of:of:

Intermediate ObjectivesIntermediate Objectives

2.1 The firefighter shall define the following units of measure:

a) British Thermal Units (BTU)b) Fahrenheit (F)c) Celsius (C)d) Calorie (C)e) Joule, the SI unit of energy 2.2 The firefighter shall define thermal

balance and imbalance.

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Define: British Thermal Unit Define: British Thermal Unit (BTU)(BTU)

A) British Thermal Unit is a unit of energy, 1876–present, usually referred to as a Btu (pronounced “bee tee u”).

Originally defined as the quantity of heat needed to raise the temperature of 1 pound avoirdupois of air-free water 1°F under a constant pressure of 1 atmosphere, starting at the temperature at which water is most dense, 39.1°F. This is about the amount of energy released when the tip of a kitchen match burns.

Since the calorie, another measure of a quantity of heat, is also defined in terms of a temperature interval and the mass of water heated, any definition of a calorie implies a definition of a Btu.

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Define: British Thermal Define: British Thermal Unit (BTU)Unit (BTU)

Name of unit Symbol Equivalent in joules

International Table Btu. Based on the definition of the International Table calorie (exactly 4.1868 J) at the Fifth International Conference on the Properties of Steam (London, July 1956).

BtuIT exactly 1055.055 852 62 joules

thermo chemical Btu. Based on the definition of the thermo chemical calorie (exactly 4.1840 joules) by the U.S. Bureau of Standards in 1953.

Btuth approximately 1054.350 joules

mean Btu. 1⁄180 of the quantity of heat needed to raise the pound of water from 32° F to 212° F

1055.87 joules

39°F Btu 1059.67 joules



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Define: FahrenheitDefine: Fahrenheit

B) Fahrenheit Pronunciation: 'far-&n-"hIt, 'fer-Daniel G. Fahrenheit

Relating or conforming to a thermometric scale on which under standard atmospheric pressure the boiling point of water is at 212 degrees above the zero of the scale, the freezing point is at 32 degrees above zero, and the zero point approximates the temperature produced by mixing equal quantities by weight of snow and common salt -- abbreviation F

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Define: CelsiusDefine: Celsius

C) CelsiusPronunciation: 'sel-sE-&s, -sh&s

Relating to, conforming to, or having the international thermometric scale on which the interval between the triple point of water and the boiling point of water is divided into 99.99 degrees with 0.01° representing the triple point and 100° the boiling point <10° Celsius> -- abbreviation C

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Define: CalorieDefine: Calorie

D) calorie Variant(s): also cal·o·ry /'ka-l&-rE, 'kal-rE/Etymology: French calorie, from Latin calor heat, from calEre to be warm

1 a : the amount of heat required at a pressure of one atmosphere to raise the temperature of one gram of water one degree Celsius that is equal to about 4.19 joules -- called also gram calorie, small calorie; abbreviation cal b : the amount of heat required to raise the temperature of one kilogram of water one degree Celsius : 1000 gram calories or 3.968 Btu -- called also large calorie; abbreviation Cal

2 a : a unit equivalent to the large calorie expressing heat-producing or energy-producing value in food when oxidized in the body b : an amount of food having an energy-producing value of one large calorie

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Define: JouleDefine: Joule

E) The unit of energy in SI. Symbol, J. The work done when the point of application of a force of 1 newton is displaced 1 meter in the direction of the force. One watt-second is equal to 1 joule.

The joule’s dimensions are force × length (newton × meter, or in terms of base units only:) meter² x kiligram

seconds²

The joule is named after James Prescott Joule (1818 – 1889), who in 1845 was the first to measure the equivalence of work and heat, by having falling weights rotate paddles in water.

The joule was adopted in 1889 by the International Electrical Congress. When the CGPM first defined SI, in 1960, it included the joule as one of the derived units.

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Define: Thermal Balance and Define: Thermal Balance and ImbalanceImbalance

When combustion occurs, heat is liberated as part of the oxidation process.

The properties of molecules are such that as heat is applied or absorbed, the molecular makeup becomes agitated.

Simply, that means the outermost boundary of the molecular collection will push outwardly and expand.

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Looking at the anatomy of heat given off by a fire, one can visualize the lighter heated air moving upwardly and the cooler air dropping to lower levels.

Firefighters knowing these significant characteristics by how and why heat moves will enable the firefighter to employ tactics that will limit extension, confine the fire, and extinguish it.

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Hot air rises from a fire and will continue to rise until it reaches equilibrium with its surrounding atmosphere.

When confined to a structure, the hotter air will accumulate on the ceiling of the room and Bank Down until it can find an escape route.

Sometimes it will bank down right to the floor.

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Watching the smoke from a fire will give us an indicator as to what is happing with the heated air.

Because the unburned particles of fuel found in smoke are affected by hot air, tracking the smoke will expose the path taken by the hot air.

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It is the physical characteristics of thermal balance and imbalance that cause smoke to column and mushroom.

The heated air and smoke rise.The hotter the air, the faster and more

violent the ascent.When the thermal balance of the air has

been reached, the ascent ceases and establishes equilibrium with the surrounding atmosphere.

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The smoke then Stratifies and begins to move horizontally in all directions from the central thermal column.

The result is a form that looks like a mushroom.

However, in a structure, the mushrooming of smoke and heat occur for different reasons.

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In a structure, the heated air meets an obstruction in the ceiling and, being unable to rise further, spreads out horizontally seeking another vertical exit.

If unable to find that exit, it banks down and compresses the volume of air in the structure.

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This compression causes air pressure within the confined structure, and any opening will show smoke and possibly fire being violently expelled with such force that it causes the smoke to roll and billow.

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Inter. Fire Behavior End Note:Inter. Fire Behavior End Note:

Personal Size-UPAlways make a

continuous mental evaluation of your immediate environment, facts, and probabilities to come home safe, and Good Luck!!!!

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Advanced Principles Advanced Principles of:of:

Advanced ObjectivesAdvanced Objectives

3.1 The firefighter shall identify chemical by-products of combustion.

3.2 The firefighter shall define diffusion flame process.

3.3 The firefighter shall define the fire extinguishment theory.

3.4 The firefighter shall identify pressure and velocity.

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Define: Diffusion Flame Define: Diffusion Flame ProcessProcess

Diffusion: A natural occurring event in which molecules travel from levels of high concentration to areas of low concentration.

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Define: Extinguishment TheoryDefine: Extinguishment Theory

The way to stop a fire is to remove one its essential ingredients.

Knowing that for self-sustaining chemical reaction we call combustion to occur, four elements are needed:

HeatFuelOxygenChemical reactionRemove one of them and the fire collapse.

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Define: Extinguishment TheoryDefine: Extinguishment Theory

More formally stated, we can say that Temperature diminution, Fuel elimination, Oxygen elimination, or Chemical flame repression will extinguish fire.

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Identify: Pressure and VelocityIdentify: Pressure and Velocity

Pressure: The force, or weight, of a substance, usually water, measured over an area.

Velocity: The forward pressure as it leaves an opening.

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Documents

1 Basic Principles of:. Basic Objectives 1.1 The firefighter shall define heat and fire. 1.2 The firefighter shall define the fire triangle and tetrahedron