Chapter 2 Flashcards
Fire dynamics
What is the study of the characteristics of fire and the burning process which includes how fires start, develop and spread?
Fire dynamics
We have two enemies what are they?
The fire and the building that is on fire
It is extremely important for your professional development and to the safety and survival of your firefighters that you understand.?
Dynamic behavior of a fire inside a building during the offense of interior attack and defensive to a lesser degree
Every fire needs three components what are they?
Fuel , heat and oxygen
Fuels are materials that store
Energy
In order to have rapid self combustion and increasing fire development, there must be a’’ to perpetuate the flaming mode of combustion
Chemical chain reaction
The spontaneous self sustained chemical chain reaction keeps the fire
Burning and growing
What is the fourth element of fire Tetrahedron
Chemical chain reaction
Fire is also referred to as’’ in as the process of’’
Combustion, rapid oxidation p. 19
The fire generates more ‘’ (radiation) , emits light ( ‘’) and releases energy as a result of that ‘’
Heat, flame, reaction
Fire colors regarding heat
Yellow-
Red
Orange
Blue
White
y- coolest
W- hottest
Fire is not a ‘’ or ‘’ it’s a byproduct of the combustion vapors that are released from solid and liquid fuels during the chemical process
Solid or liquid
What is every physical object that you see in everything that exist in the universe?? Anything that occupies space has mass, size weight or volume
Matter
In science matters made up of atoms and molecules that exist in three states which are
Solids, liquids, and gases
Oxidation is commonly seen as
Rust
The one that framed this house is made up of materials called
cellulose
Substances that originate from living organisms are referred to as
Organic compounds
Organic compounds usually contain elements of
Carbons, hydrogen and oxygen
Hydrocarbons are also
Organic compounds
Plastics were never alive, but they were made from oil(hydrocarbons) which were once?
Prehistoric life forms that have been dead decaying for millions of years thus once living
Oil companies drill for once living materials and through their chemical processes creating nonliving material. The end results are.
Plastics, petroleum, diesel, and gasoline products
Matter in the universe that has never been alive or part of a living organism is called
In organic
Minerals like iron, quartz, and granite are examples of
Organic compounds
Difference between organic and inorganic materials are
Organic materials will burn
Smallest unit of matter is
An atom
Atoms are made made of
Protons, neutrons and electrons p. 20
Adams become chemically stable by gaining, losing or sharing electrons with other atoms to fill their
outer most shell
Adams join to form
Molecules
The most common example of two oxygen atoms joining to form an oxygen molecule is written as
02
Almost all fuels consistent
Hydrogen and carbon hence why they’re called hydrocarbons
The atomic glue that holds these molecules together is called day
Bond
When Adams and molecules join together, a certain amount of heat is absorbed to the bond which creates and holds together the newly formed Element this process is called
Endothermic reaction the heat is absorbed when the bond is created
When the bond is, fortunately, broken energy is released in the form of heat and light and
Exothermic reaction
an ‘’ act as a catalyst to break down what otherwise would remain a stable molecule
Oxidizer
Most common oxidizer available is
Oxygen
the ‘’ possesses a chemical property that can pull apart and break up the bottom that previously existed
Oxidizer processes p. 21
A lite coat of ‘’ applied on metal prevents rusting because air is unable to come into direct contact with the surface of the metal so it cannot reach and’’ the metal
oil , oxidize
The presence of oxygen and combination with heat from a previous bond breaking causes a rapid reaction to take place, which is
Exothermic reaction
When energy intensifies which causes additional molecular bonds to break apart and so on until a rapid spontaneous self-sustaining chain reaction occurs is a process called
Combustion
Chemical reaction occurring during combustion is called
Oxidation
The amount of oxygen presents affects the process and speed of oxidation as well as the process and speed of combustion. It can be very slow as ‘’ or they can make her very fast as in //
rust /explosion
In earths atmosphere the normal concentration of oxygen is approximately’’, nitrogen’’, water vapor, neon, carbon dioxide, and other gases ‘’
o-21 %
N-78
O- 1
Combustion occurs in oxygen concentration between ?
14 and 100%
And atmospheres were oxygen concentration is below 4% combustion can
Not occur
He is the most common source of what on earth
Energy
Heat forges atoms and molecules together to form compounds(‘’) , and heat is released when those bonds are separate( ‘’)
Endothermic reaction
Exothermic reaction
Heat is a form of energy that consists of
Matter in motion
There are five basic sources of heat energy. What are they?
Chemical, electrical, mechanical, solar, and nuclear. common sources of everyday heat p. 22
What is the breaking down of molecular compound
Decomposition or pyrolysis
Mechanical heat source is caused by’’ which is the breakdown of two materials that are compressed together or rapidly rubbed against each other
Friction
Heat buildup from friction as often the cause of fires in ?
machinery p. 22
An electrical heat source can occur several ways: which are
current flowing through a resistance, overcurrent or overload, arching, sparking, static charge, and lightning.
As a general rule, the heavier in the material the more efficient it is as a
Conductor, that’s why metal is a good conductor
what electricity occurs when two different materials are rubbed together, scraped together or a suddenly joined or separated. These actions create energy in the form of mechanical heat, but on a molecular level.
static
The static charges small is small. They can be seen with the naked eye nevertheless it is very powerful and can reach temperatures in excess of.
2000°
What is static electricity on a grand scale that can generate heat energy in excessive’’
Lightning, 60,000°
What is created when flammable liquids are transferred from one storage container to another and has been the ignition source for many flammable fires. This is why fuel tankers and aircraft have to be properly grounded and bonded by wires during fueling and fuel transfer operations. It is not necessary when filling your car at the gas station because gasoline no special additives that make it feel act as a ground
Static electricity
The most powerful and most common source of human energy
Solar
The understood energy by the general republic
Nuclear
Many US military ships and submarines are powered by
Nuclear energy
What is created by splitting the nucleus of an atom into two smaller nuclei or by combining two small nuclei into a large nucleus
Nuclear when incase in a heavy’’ shield called the ‘’ radioactive safely confined. p. 23
What happened with the nuclear plant explosion in Chernobyl .
The meltdown of the core occurred when the water levels was too low to keep up with it heat once without a coolant the rods are no control and run away. Reaction occurred.
Heat causes
Parolysis
Heat causes the continuous production and ignition of fuel vapors so that combustion can
Continue
What is the application of continuous force by one object against another object that it touches?
Pressure
what is the measurable amount of pressure exerted by a liquid as a converts to a gas and exerts pressure against the side of a confined closed container
Vapor pressure
What is the weight of a material and depends on the number of molecules and atoms that occupied given volume? The more molecules and given volume the ‘’ its material.
Density
Denser material the greater is its ability to
Conduct heat
A collection of molecules that accompany a space in a filled state that not to separate is a
Liquid
Some molecules are re-absorbed into the liquid while other others remain in a cases stayed within the container. This process is called.
Diffusion
If gases are lighter than air and aren’t combined inside the container, all the liquid will eventually
Evaporate
If the gas is heavier than the molecules remains suspended in the space between the surface of the liquid and the top of the container. Even in an open container at this point where there are many molecules being liberated from the liquid as being re-absorbed by liquid, it is referred to as the state of
Equilibrium
Cooling the containers inhibits the liquids ability to
Diffuse
What is the weight of a gas compared to normal air?
Vapor density
The normal atmospheric pressure of air at sea level is’’ given the designated number of ‘’ when measured at 32°
14.7 psi…. 1
Gas that weighs less than the same volume of air are lighter than air and tend to ‘’.. Their vapor density is designated as a number less than ;’’’
Rise ,1
Two flammable gases that we encounter frequently in the fire service are
Methane ( natural gas) and propane p.24
Methane is a vapor density of
0.6 making it lighter than normal air
Methane released into the open air will
Rise
With accidental releases inside a structure, the gas will rise and accumulate at the highest point then start to back down. This is why it is so important to what with natural gas leaks inside structure.
Ventilate high and eliminate sources of ignition
Propane has a vapor density of
1.6 making it heavier than air so it sinks
When using a gas detector and a propane leak
Take the readings and low areas close to the source because it’s heavier than air
If a liquid is flammable and stored under pressure like propane, the bottom, half of the container is liquid propane, while the top half of the container is
Vaporize propane
If this pressure is container subject to the heat from fire, the rabbit pressure both up can exceeded the relief valves ability to vent the flammable vapor safely, which can ultimately lead to
BLeve p. 25
Even if the liquid and vessel is not flammable, the container rupture can still be violent, resulting in a force that can send container fragments and sharpnels great distance as far as
1/2 miles
What is a strategy to prevent a BLEVE
Cool the top of the tank that contains all the pressurized vapor with water
If a reliable water source cannot be maintained or if the risk factors too great another tactic would be too
Evacuate the area and let it burn
The most common example of a BLEVE IS
Popping a popcorn p. 26
All materials will be the laws of physics and exist in one of the three states
Solids, liquids, or gases
The state of conversion from a liquid to a gas under normal atmosphere conditions is called
Evaporation
Combustion can take place only when a substance is in what state
Gas
If there isn’t enough combustible, gas presented to ignite the mixture it said to be too ‘’ to burn
lean
If there’s too much gas presented or the concentration to exceeds, it is said to be too ‘’ to burn
Rich
A concentration of gas falls into the range where it can ignite. It is said to be within its
Flammable or explosive limit
The lower end of flammable or explosive ignition is called
Lower explosive limit
The higher end of flammable explosion ignition is called
Upper explosive limit
Atmospheres that are below what oxygen requires the use of SCBA;s
19%
The flammable range of CO is between
12.5 - 74 %
The flammable range for natural gas is between
6.5% and 17%
The flammable range for gasoline is between
1.5% and 7.6%
CO has a much greater range to ignite then
Natural gas and gasoline
Over the years fire behavior, scientist defined the burning stages of fire as following
Ignition stage
Growth stage
Fully developed stage
decay Stage p. 27 `
What type of windows often are the heat of the fire during the ignition and growth stage without failing ?? Which also provide the fire with additional air
Double and triple pane glass for insulation
Two new stages and fire growth has led to the development of the six stage, ventilation control fire growth model, which is ?
Ignition
Initial growth stage
Ventilation limited stage
Explosive growth stage
Fully developed stage
Decays stage p. 28
When a combustible material heats up, it starts to liberate gases that can burn. The initial heat source usually comes from an external origin, such as a flame or spark for my fire that has already burned. The heat source can also come from. x3
Radiation conduction, or convection
Simply put what stage of a fire is the point at which four elements of the fire tetrahedron come together?
Ignition stage
What stage is typically small, limited in surface area and easy to control and extinguish
Ignition stage
