Chapter 3 Fire Behavior

The freezing and boiling points of water in the Celsius scale are ___ degrees and ___ degrees. (90)

0, 100

When water is converted to steam, it expands approximately ___ times. (131)

1700

Normally, air consists of how much oxygen? (103)

21%

Pyrolysis begins at temperatures below ___. (100)

400 DEGREES FAHRENHEIT (204 DEGREES CELSIUS)

A chemical reaction occurs when ___. (87)

A SUBSTANCE CHANGES FROM ONE TYPE OF MATTER TO ANOTHER

While not generally used for extinguishment in structure fires, limiting the fire's ___ can be a highly effective fire control action. (132)

AIR SUPPLY (VENTILATION)

The simplest method of fuel removal is to allow what to happen? (131)

ALLOW THE FIRE TO BURN UNTIL THE FUEL IS CONSUMED

Combustion is a ___. (87)

AN EXOTHERMIC CHEMICAL REACTION THAT IS A SELF-SUSTAINING PROCESS OF RAPID OXIDATION OF A FUEL, THAT PRODUCES HEAT AND LIGHT

Class B fires can be extinguished with ___. (110)

APPROPRIATELY APPLIED FOAM AND/OR DRY CHEMICALS

___ ignition temperature is the temperature to which the surface of a substance must be heated for ignition and self-sustained combustion to occur. (90)

AUTO

___ ignition without any external flame or spark to ignite the fuel gases or vapors. (90)

AUTO

___ is the instantaneous explosion or rapid burning of superheated gases that occurs when oxygen is introduced into an oxygen-depleted confined space. (122)

BACKDRAFT

The ___ is the amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit. (89)

BTU

Organic fuels contain ___, inorganic fuels do not. (96)

CARBON

___ is a colorless, odorless, heavier than air gas that neither supports combustion nor burns. (108)

CARBON DIOXIDE

___ is a colorless, odorless, dangerous gas formed by the incomplete combustion of carbon. (108)

CARBON MONOXIDE

___ is likely the most common fire gas. (108)

CARBON MONOXIDE

Flaming combustion is an example of a ___. (106)

CHEMICAL CHAIN REACTION

___ energy is the most common source of heat in combustion reactions. (91)

CHEMICAL HEAT

An exothermic heat reaction is a ___. (87)

CHEMICAL REACTION BETWEEN TWO OR MORE MATERIALS THAT CHANGES THE MATERIALS AND PRODUCES HEAT, FLAMES, AND TOXIC SMOKE

An endothermic chemical reaction is a ___. (87)

CHEMICAL REACTION IN WHICH A SUBSTANCE ABSORBS HEAT ENERGY

Class D fires involve ___. (111)

COMBUSTIBLE METALS

As a firefighter, you need to understand the ___ process and how fire behaves in different materials and in different ___. (85)

COMBUSTION, ENVIRONMENTS

A ___ is defined as a fire that occurs within an enclosed room or space within a building. (112)

COMPARTMENT FIRE

When extinguishing Class C fires, make sure extinguishing agent does not ___. (111)

CONDUCT ELECTRICITY

___ is the transfer of heat within a body or to another body by direct contact. (94)

CONDUCTION

___ is the transfer of heat energy from a fluid to a solid surface. (95)

CONVECTION

Solid fuels and liquid fuels with high flash points can be extinguished by ___. (130)

COOLING

The primary mechanism of extinguishment with Class A fires is ___. (110)

COOLING

___ depends on reducing the temperature of a fuel to the point where it does not produce a sufficient vapor to burn. (130)

COOLING

When possible, ___ on Class C fires before extinguishing efforts begin. (111)

DE-ENERGIZE ELECTRICAL EQUIPMENT

The ___ stage of fire development is when fuel is consumed and energy release diminishes, and temperatures decrease. (121)

DECAY

At normal oxygen levels, Nomex ___ (104)

DOES NOT BURN

Class C fires involve ___. (110)

ENERGIZED ELECTRICAL EQUIPMENT

Class B fires involve ___. (110)

FLAMMABLE AND COMBUSTIBLE LIQUIDS AND GASES

___ is the temperature at which a liquid gives off sufficient vapors to ignite, but not sustain, combustion. (98)

FLASH POINT

___ is the rapid transition between the growth and the fully developed fire stages. (118)

FLASHOVER

If a building is not properly ventilated, any of the following can happen. (86)

FLASHOVER, BACKDRAFT, OR SMOKE EXPLOSION

Removing the ___ effectively extinguishes any fire. (131)

FUEL SOURCE

The ___ stage of burning process is where enrgy release is at maximum rate and is limited only by availability of fuel and oxygen. (121)

FULLY DEVELOPED

The ___ stage is the early stage of a fire during which fuel and oxygen are virtually unlimited. (116)

GROWTH

The principle of ___ is the reason that SCBA cylinders feel warm after they have been filled. (93)

HEAT OF COMPRESSION

___ is generated when a gas is compressed. (93)

HEAT OF COMPRESSION

The movement of two surfaces against each other creates ___. (93)

HEAT OF FRICTION

Of the general types of combustion products, which have the most impact on firefighters? (107)

HEAT, SMOKE

Three general type of products of combustion are ___. (107)

HEAT, SMOKE, AND LIGHT

For a fire to develop there must be enough air available to support burning beyond the ___ stage. (127)

INCIPIENT

The ___ stage is the first stage of the burning process. (114)

INCIPIENT

Fire development stages in a compartment include ___. (113)

INCIPIENT, GROWTH, FULLY DEVELOPED, DECAY

Since electricity does not burn, the fuel in a Class C fire is usually ___ or ___. (111)

INSULATION ON WIRING, LUBRICANTS

___ energy is the energy possessed by a moving object. (89)

KINETIC

Class K fires involve ___. (112)

KITCHEN GREASES AND OILS

A firefighter's ability to predict what will happen in the fire environment may be hampered by ___. (85)

LIMITED INFORMATION, TIME PRESSURE, AND OUR LEVEL OF UNDERSTAND OF FIRE BEHAVIOR.

In thermal layering the cooler gases tend to be in the ___ layer. (117)

LOWER

The ___ is the minimum concentration of fuel vapor and air that supports combustion (105)

LOWER FLAMMABLE LIMIT

___ is generated by friction or compression. (93)

MECHANICAL HEAT ENERGY

Materials that are ___ in water will mix in any proportion. (99)

MISCIBLE

Materials that burn at normal oxygen levels will burn ___ in oxygen-enriches atmospheres. (104)

MORE INTENSELY AND MY IGNITE MORE READILY

A fire in a large compartment will develop ___ than one in a small compartment. (127)

MORE SLOWLY

The interface of the hot and cooler gas layers at the opening is commonly referred to as the ___. (117)

NEUTRAL PLANE

Some solid fuels can undergo oxidation at the surface of the fuel. This is called ___. (87)

NONFLAMING COMBUSTION

Class A fires involve ___. (110)

ORDINARY COMBUSTIBLE MATERIALS

___ are not combustible but like oxygen, they will support combustion. (103)

OXIDIZERS

Reducing the ___ available to the combustion process reduces a fire's growth and may totally extinguish it over time. (131)

OXYGEN

The fire triangle consists of all of the following. (87)

OXYGEN, FUEL, HEAT

The fire tetrahedron consists of all of the following. (87)

OXYGEN, FUEL, HEAT, SELF-SUSTAINED CHEMICAL REACTION

___ are materials that absorb heat but do not participate actively in the combustion reaction. (96)

PASSIVE AGENTS

To understand fire, basic concepts from ___ must be understood. (86)

PHYSICAL SCIENCE

Physical science includes the sciences of ___ and ___. (86)

PHYSICS, CHEMISTRY

___ ignition occurs when a mixture of fuel and oxygen encounter an external heat source with sufficient heat energy to start the combustion reaction. (90)

PILOTED

___ energy is stored energy possessed by an object that can be released in the future to perform work. (89)

POTENTIAL

Energy exists in two states, ___ and ___. (89)

POTENTIAL, KINETIC

Combustible metals are especially hazardous in their ___ form. (111)

POWDERED

___ is the chemical decomposition of a substance through the action of heat. (90)

PYROLYSIS

___ is the transmission of energy as an electromagnetic wave without and intervening medium. (95)

RADIATION

Fuel in a combustion reaction is known as the ___. (96)

REDUCING AGENT

Firefighters need an understanding of fire behavior that permits them to recognize developing fire conditions and be able to ___. (85)

RESPOND SAFELY AND EFFECTIVELY TO MITIGATE THE HAZARDS PRESENTED BY THE FIRE ENVIRONMENT.

___ describe a condition where the unburned fire gases accumulated at the top of a compartment ignite and flames propagate through the hot gas layer or across the ceiling. (118)

ROLLOVER (FLAMEOVER)

The main mechanism of extinguishment for Class K fires is ___.

SAPONIFICATION

___ is a form of extinguishment where extinguishing agents turn fats and oils into a soapy foam that extinguishes the fire.

SAPONIFICATION

The ___ and ___ are the factors that separate flaming combustion from slower oxidation reactions. (106)

SELF-SUSTAINED CHEMICAL REACTION, RELATED RAPID GROWTH

Liquids have mass and volume, but no definite ___ (except for a flat surface). (97)

SHAPE

Gases have mass but no definite ___ or ___. (97)

SHAPE, VOLUME

Self-heating is also known as ___. (91)

SPONTANEOUS HEATING

Preexisting ventilation is the actual and potential ventilation of a structure based on ___. (128)

STRUCTURAL OPENINGS, CONSTRUCTION TYPE, BUILDING VENTILATION SYSTEMS

What are the three main things happening within the burning compartment just before flashover? (120)

TEMPERATURES ARE RAPIDLY INCREASING, ADDITIONAL FUEL IS BECOMING INVOLVED, FUEL IN THE COMPARTMENT IS GIVING OFF COMBUSTIBLE GASES BECAUSE OF PYROLYSIS

An example of slow oxidation is ___. (87)

THE COMBINATION OF OXYGEN WITH IRON TO FORM RUST

An example of rapid oxidation is ___. (87)

THE COMBUSTION OF METHANE

The "surface-to-mass ratio" is defined as. (101)

THE SURFACE AREA OF THE FUEL IN PROPORTION TO THE MASS

The ___ of gases is the tendency of gases to form into layers according to temperature. (117)

THERMAL LAYERING

In thermal layering the hottest gases tend to be in the ___ layer. (117)

TOP

According to NFPA 1001, those qualified at the Fire Fighter I level must know all of the following EXCEPT. (86)

TYPES OF BUILDING CONSTRUCTION

Many people believe that fire is ___. (85)

UNPREDICTABLE

When fire development is limited by air supply, the fire is said to be ___. (113)

VENTILATION CONTROLLED

A physical change occurs when a substance ___. (87)

WHEN A SUBSTANCE REMAINS CHEMICALLY THE SAME BUT CHANGES IN SIZE, SHAPE, OR APPEARANCE

Resistance heating is defined as ___. (92)

WHEN ELECTRIC CURRENT FLOWS THROUGH A CONDUCTOR, PRODUCING HEAT

If a window fails or a door is opened on the ___ side of the building, fire intensity and spread can increase significantly. (129)

WINDWARD

___ occurs when a force is applied to an object over a distance. (89)

WORK

Heat can be transferred from one body to another by what three mechanisms? (93)

a. conduction b. convection c. radiation

When first arriving on scene, what are main concerns to a firefighter? (86)

a. smoke and flames may be threatening to trapped occupants b. fire may spread to another structure or group of structures c. the room in which the fire started may be close to flashover