Exam 5 2023

Question 1

Question 1:

Which 10-41 code is incorrect?

A: Code 1: Occupied Structure or Vehicle- A structure (commercial, residential, public), or vehicle (car, bus or train) which is occupied at the time of the fire. This also includes a vacant apartment in an occupied building, or a store with a dwelling above, or an occupied detached garage, shed or similar structure.

B: Code 2: Unoccupied Structure- A structure (commercial, residential, public), normally occupied which is unoccupied at the time of the fire.

C: Code 3: Unoccupied Vehicle- A vehicle, (car, bus or train) with or without plates, which is unoccupied at the time of the fire.

D: Code 4: Vacant Structure, or Structures always intended for Dwelling Purposes. Examples include, but are not limited to the following: Vacant buildings, buildings under construction/demolition, detached garages, sheds or similar structures

Answer 1

A: Code 1: Occupied Structure or Vehicle- A structure (commercial, residential, public), or vehicle (car, bus or train) which is occupied at the time of the fire. This also includes a vacant apartment in an occupied building, or a store with a dwelling above, or an occupied detached garage, shed or similar structure.

B: Code 2: Unoccupied Structure- A structure (commercial, residential, public), normally occupied which is unoccupied at the time of the fire.

C: Code 3: Unoccupied Vehicle- A vehicle, (car, bus or train) with or without plates, which is unoccupied at the time of the fire.

D:✔Code 4: Vacant Structure, or Structures always intended for Dwelling Purposes. Examples include, but are not limited to the following: Vacant buildings, buildings under construction/demolition, detached garages, sheds or similar structures

Explanation:
Code 4: Vacant Structure, or Structures NOT intended for Dwelling Purposes. Examples include, but are not limited to the following: Vacant buildings, buildings under construction/demolition, detached garages, sheds or similar structures

Question 2

Question 2:

The new FDNY manual Fire Dynamics writes about the Chemistry of Fire. Which statement is incorrect regarding this bulletin?

A: The term “fire” refers to how something burns. Fire is a rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities.

B: Fire and combustion are similar conditions; however, combustion can occur without fire.

C: Combustion is a chemical process of oxidation that occurs at a rate slow enough to produce heat and usually light in the form of either a glow or flame.

D: There are two modes of combustion, non-flaming and flaming. Non-flaming combustion occurs more slowly and at a lower temperature producing a smoldering glow in the material’s surface without flames.

Explanation:
Training Bulletins- Fire Dynamics ch 1 sec 2.1-2.3
Combustion is a chemical process of oxidation that occurs at a rate FAST enough to produce heat and usually light in the form of either a glow or flame.
Flaming Combustion: Flaming combustion is commonly referred to as fire because it produces a visible flame above the material’s surface.

Answer 2

A: The term “fire” refers to how something burns. Fire is a rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities.

B: Fire and combustion are similar conditions; however, combustion can occur without fire.

C:✔Combustion is a chemical process of oxidation that occurs at a rate slow enough to produce heat and usually light in the form of either a glow or flame.

D: There are two modes of combustion, non-flaming and flaming. Non-flaming combustion occurs more slowly and at a lower temperature producing a smoldering glow in the material’s surface without flames.

Explanation:
Training Bulletins- Fire Dynamics ch 1 sec 2.1-2.3
Combustion is a chemical process of oxidation that occurs at a rate FAST enough to produce heat and usually light in the form of either a glow or flame.
Flaming Combustion: Flaming combustion is commonly referred to as fire because it produces a visible flame above the material’s surface.

Question 3

Question 3:

Research into fire behavior has determined that an uninhibited chemical chain reaction must also be present in addition to the other elements of the fire triangle (fuel, oxygen & heat) in order for flames to occur. Therefore, the _______ was created to explain flaming combustion. Each element of the fire tetrahedron; fuel, oxygen, heat & uninhibited chemical chain reaction must be present for flaming combustion. Removing any element of the tetrahedron interrupts the chemical chain reaction and stops flaming combustion.

A: fire triangle

B: fire tetrahedron

C: fire dynamic

D: fire flamer

Answer 3

A: fire triangle

B:✔fire tetrahedron

C: fire dynamic

D: fire flamer

Explanation:
Fire Dynamics Ch 1 sec 2.4.1
Fire Triangle: The oldest and simplest model, the fire triangle, illustrates the three elements necessary for combustion to occur: fuel, oxygen and heat. Remove any one of these elements and combustion will cease. The fire triangle best illustrates the elements required for non-flaming combustion; when burning is localized on or near the fuel’s surface where it is in contact with oxygen. Examples of non-flaming combustion include burning charcoal briquettes or smoldering wood or fabric.

Question 4

Question 4:

Fuel may be found in any of three states of matter; solid, liquid, or gas. Only gases burn. In order for a solid or liquid to burn, they must be converted into a gas. Solids are converted into gas by _____ and Liquids are converted to a gas by _____.

A: pyrolysis, vaporization

B: permeation, vaporization

C: pyrolysis, evaporation

D: permeation, evaporation

Answer 4

A:✔pyrolysis, vaporization

B: permeation, vaporization

C: pyrolysis, evaporation

D: permeation, evaporation

Explanation:
Fire Dynamics ch 1 sec 2.5.1

Question 5

Question 5:

Oxygen in the air is the primary oxidizing agent in most fires. Normally, air consists of 20.8% oxygen. At normal ambient temperatures, materials can ignite and burn at oxygen concentrations as low as ________.

A: 18 percent.

B: 17 percent.

C: 16 percent.

D: 15 percent.

Answer 5

A: 18 percent.

B: 17 percent.

C: 16 percent.

D:✔15 percent.

Explanation:
Fire dynamics ch 1 sec 2.6.1

Question 6

Question 6:

A number of natural laws of physics are involved in the transmission of heat. One is called the ________; it specifies that heat always flows from a hot substance to a cold substance. The colder of two objects in contact with each other will absorb heat until both objects are at the same temperature.

A: Law of Averages

B: Law of Heat Averages

C: Law of Average Flow

D: Law of Heat Flow

Answer 6

A: Law of Averages

B: Law of Heat Averages

C: Law of Average Flow

D:✔Law of Heat Flow

Explanation:
Fire Dynamics Ch 1 sec 2.7.1

Question 7

Question 7:

After memorizing this photo for four minutes, click yes and answer the following 9 questions.

A: Yes

Question 8

Question 8:

How many people are in the picture?

A: 3

B: 4

C: 5

D: 6

Answer 8

A: 3

B: 4

C:✔5

D: 6

Question 9

Question 9:

How many people are wearing sneakers?

A: 1

B: 2

C: 3

D: 4

Answer 9

Question 9:
How many people are wearing sneakers?
A: 1

B:✔2

C: 3

D: 4

Question 10

Question 10:

Which is incorrect regarding this photo?
A: The gentleman wearing the green sweater has a collared shirt on underneath

B: Two of the five people are wearing collared clothing

C: One of the five books is yellow

D: Two women have their legs crossed

Answer 10

A: The gentleman wearing the green sweater has a collared shirt on underneath

B:✔Two of the five people are wearing collared clothing

C: One of the five books is yellow

D: Two women have their legs crossed

Explanation:
Four of the five people are wearing collared clothing

Question 11

Question 11:

How many people are wearing glasses?

A: 1

B: 2

C: 3

D: 4

E: All of them

Answer 11

A: 1

B:✔2

C: 3

D: 4

E: All of them

Question 12

Question 12:

True or False… Every book is a different color

A: True

B: False

Answer 12

A:✔True

B: False

Question 13

Question 13:

What are the people sitting on?

A: Colorful sofa

B: Bland sofa

C: Stools

D: Chairs

Answer 13

A: Colorful sofa

B: Bland sofa

C:✔Stools

D: Chairs

Question 14

Question 14:

Which is correctly stated?

A: The only green color in the entire picture is a sweater

B: The only person wearing open toed shoes is the girl to the right

C: The only person wearing red pants is the one reading a red book

D: Only one person is wearing a hat.

Answer 14

A:✔The only green color in the entire picture is a sweater

B: The only person wearing open toed shoes is the girl to the right

C: The only person wearing red pants is the one reading a red book

D: Only one person is wearing a hat.

Explanation:
B. The only person wearing open toed shoes is the girl in the middle
C. He’s reading a purple book
D. No one is wearing a hat.

Question 15

Question 15:

Which color book is not found in this photo?

A: Red

B: Yellow

C: Blue

D: Purple

E: Orange

Answer 15

A: Red

B: Yellow

C: Blue

D: Purple

E:✔Orange

Question 16

Question 16:

True or false… Everyone has their eyes looking at the book they are reading.
A: True

B: False

Answer 16

A:✔True

B: False

Question 17

Question 17:

_______ describes heat transfer through the movement of heat waves. Heat and light waves will cause radiated heat to travel through a space until it reaches an object.

A: Radiation

B: Convection

C: Conduction

D: Induction

Answer 17

A:✔Radiation

B: Convection

C: Conduction

D: Induction

Explanation:
Fire Dynamics Ch 1 sec 2.7
Heat can travel throughout a building by one or more of three methods: conduction, convection, and radiation.
Convection: Convection is the transfer of heat by the movement of air or liquid. When water is heated in a container, it expands and grows lighter, hence, the upward movement.
Conduction: Heat may be conducted from one body to another by direct contact of two objects or by an intervening heat-conducting medium (material). An example of this type of heat transfer is a cellar fire that heats pipes enough that the pipes ignite the wood inside walls remote from the fire. Another example is firefighters crawling on a hot floor that burn their knees.

Question 18

Question 18:

True or False… Reducing the oxygen content in an area also extinguishes the fire. Reduction of the oxygen content can be accomplished by flooding an area with an inert gas, such as carbon dioxide, which displaces the oxygen; or the oxygen can be reduced by separating the fuel from the air such as by blanketing it with foam or placing a cover on a pot. Both of these methods work on those rare fuels that are self-oxidizing.

A: True

B: False

Answer 18

A: True

B:✔False

Explanation:
NONE of these methods work on those rare fuels that are self-oxidizing.
Fire Dynamics Ch 1 sec 3.4

Question 19

Question 19:

Which definition is incorrectly written?

A: FLASH POINT- The highest temperature of a liquid at which that liquid gives off sufficient vapors to ignite but will not continue to burn.

B: FLAMMABLE LIQUID- A flammable liquid is a liquid that has a flash point below 100’F

C: COMBUSTIBLE LIQUID- A combustible liquid is a liquid that has a flash point equal to or greater than 100’F.

D: FIRE POINT- Fire point is the lowest temperature at which a liquid will ignite and achieve sustained burning.

E: VAPOR PRESSURE- Vapor pressure is the ability of a liquid or solid fuel to vaporize. The higher the vapor pressure, the more vapors are released (the easier it is to off-gas).

Answer 19

A:✔FLASH POINT- The highest temperature of a liquid at which that liquid gives off sufficient vapors to ignite but will not continue to burn.

B: FLAMMABLE LIQUID- A flammable liquid is a liquid that has a flash point below 100’F

C: COMBUSTIBLE LIQUID- A combustible liquid is a liquid that has a flash point equal to or greater than 100’F.

D: FIRE POINT- Fire point is the lowest temperature at which a liquid will ignite and achieve sustained burning.

E: VAPOR PRESSURE- Vapor pressure is the ability of a liquid or solid fuel to vaporize. The higher the vapor pressure, the more vapors are released (the easier it is to off-gas).

Explanation:
Fire Dynamics Ch 1 sec 6
FLASH POINT- The LOWEST temperature
There is also… VAPOR DENSITY- The vapor density of gas refers to its density compared to air. Gases that have a vapor density around 1 will mix evenly with air. A gas with a vapor density greater than 1 is heavier than air. It will sink and collect in low areas. Gases that have vapor densities less than 1 are lighter than air and will rise to the top of a compartment

Question 20

Question 20:

EXPLOSIVE RANGE (aka Flammable Range) is the range of gas to air mixtures in which ignition can occur. It is the range of gas to air mixture that exists between the lower explosive limit and the upper explosive limit. What is the explosive range of natural gas?

A: 12.5-74%

B: 5-15%

C: 1.2-99%

D: Always in explosive range

Answer 20

A: 12.5-74%

B:✔5-15%

C: 1.2-99%

D: Always in explosive range

Explanation:
Fire Dynamics ch 1 sec 7.4

Question 21

Question 21:

When does the fire scene becomes a crime scene?

A: When the Incident Commander (battalion chief or above) declares the fire to be incendiary (intentionally set).

B: When the Incident Commander (any officer rank) declares the fire to be incendiary (intentionally set).

C: When the NYPD Arson Squad declares the fire to be incendiary (intentionally set).

D: When the Fire Marshals declare the fire to be incendiary (intentionally set).

Answer 21

A: When the Incident Commander (battalion chief or above) declares the fire to be incendiary (intentionally set).

B: When the Incident Commander (any officer rank) declares the fire to be incendiary (intentionally set).

C: When the NYPD Arson Squad declares the fire to be incendiary (intentionally set).

D:✔When the Fire Marshals declare the fire to be incendiary (intentionally set).

Explanation:
AUC 317 sec 3

Question 22

Question 22:

Units just battled a 3 alarm taxpayer fire that was deemed suspicious. Which statement below would be considered incorrect according to crime scene operations?

A: If it is necessary to leave the scene prior to the fire marshals arrival, a firefighter or unit fulfilling a watchline is sufficient to maintain F.D. control of the premise.

B: Units should use tape or barriers to limit cross-contamination of the fire scene when it is deemed suspicious prior to the arrival of the marshals.

C: When a fire has been deemed undetermined it isn’t a police investigation, but if deemed suspicious they have in fact initiated a police investigation.

D: If the fire is determined by the marshals to be incendiary, it becomes a criminal investigation.

Answer 22

A: If it is necessary to leave the scene prior to the fire marshals arrival, a firefighter or unit fulfilling a watchline is sufficient to maintain F.D. control of the premise.

B: Units should use tape or barriers to limit cross-contamination of the fire scene when it is deemed suspicious prior to the arrival of the marshals.

C:✔When a fire has been deemed undetermined it isn’t a police investigation, but if deemed suspicious they have in fact initiated a police investigation.

D: If the fire is determined by the marshals to be incendiary, it becomes a criminal investigation.

Explanation:
AUC 317 sec 6.3
Units at the scene must realize that when a fire has been deemed suspicious or undetermined and the marshals are called to respond they have in fact initiated a police investigation.

Question 23

Question 23:
When does the fire scene becomes a crime scene?
A: When the Incident Commander (battalion chief or above) declares the fire to be incendiary (intentionally set).

B: When the Incident Commander (any officer rank) declares the fire to be incendiary (intentionally set).

C: When the NYPD Arson Squad declares the fire to be incendiary (intentionally set).

D: When the Fire Marshals declare the fire to be incendiary (intentionally set).

Answer 23

A: When the Incident Commander (battalion chief or above) declares the fire to be incendiary (intentionally set).

B: When the Incident Commander (any officer rank) declares the fire to be incendiary (intentionally set).

C: When the NYPD Arson Squad declares the fire to be incendiary (intentionally set).

D:✔When the Fire Marshals declare the fire to be incendiary (intentionally set).

Explanation:
AUC 317 sec 3

Question 24

Question 24:

The examination of fire scenes should be conducted according to consistent procedures that include the policy that all fire scenes be treated as a potential crime scene until the existence of an accidental cause is identified. This will insure that legal requirements for the admissibility of evidence are satisfied in cases determined to be criminal in nature. Which of the following statements is incorrectly stated?

A: The express purpose of the Fourth Amendment is to safeguard individuals against unreasonable search and seizure or invasion of privacy without consent, a valid search warrant or exigent circumstances.

B: A fire would create such an exigent circumstance in which the F.D. does not require a warrant or consent to enter a burning building to mitigate the emergency. The threat of rekindle presents another exigency that would justify warrantless and non consensual investigation into the cause and origin of the fire. Preservation and control of the scene and examination may continue for a reasonable time period during which the investigator may seize physical evidence as appropriate under the Plain View Doctrine and preserve these items.

C: Subsequent re-entry by investigators, after F.D. units leave the scene, to determine the cause and origin may require an administrative search warrant. To obtain this, marshals need only to show that a fire of undetermined origin had occurred in a premise and the search will be limited to the areas relevant to the determination of cause and origin. This administrative warrant requirement is eliminated if F.D. units maintain control of the scene until the fire marshals arrival.

D: If evidence of criminal activity is discovered during the course of an investigation it may be used to obtain a criminal search warrant to gather further evidence of arson.

E: Members operating at the scene should realize there are major liabilities involved in discarding potential evidence (out windows, etc.) during the course of operations or overhauling. As professionals we should strive to assist marshals in their investigation by relaying these details to facilitate reconstruction of the scene and the proper placement of potential evidence.

Answer 24

A: The express purpose of the Fourth Amendment is to safeguard individuals against unreasonable search and seizure or invasion of privacy without consent, a valid search warrant or exigent circumstances.

B: A fire would create such an exigent circumstance in which the F.D. does not require a warrant or consent to enter a burning building to mitigate the emergency. The threat of rekindle presents another exigency that would justify warrantless and non consensual investigation into the cause and origin of the fire. Preservation and control of the scene and examination may continue for a reasonable time period during which the investigator may seize physical evidence as appropriate under the Plain View Doctrine and preserve these items.

C: Subsequent re-entry by investigators, after F.D. units leave the scene, to determine the cause and origin may require an administrative search warrant. To obtain this, marshals need only to show that a fire of undetermined origin had occurred in a premise and the search will be limited to the areas relevant to the determination of cause and origin. This administrative warrant requirement is eliminated if F.D. units maintain control of the scene until the fire marshals arrival.

D: If evidence of criminal activity is discovered during the course of an investigation it may be used to obtain a criminal search warrant to gather further evidence of arson.

E:✔Members operating at the scene should realize there are major liabilities involved in discarding potential evidence (out windows, etc.) during the course of operations or overhauling. As professionals we should strive to assist marshals in their investigation by relaying these details to facilitate reconstruction of the scene and the proper placement of potential evidence.

Explanation:
there are NO liabilities involved in discarding potential evidence
This was a wordy question for a reason. There’s a lot of good info here.
AUC 317 sec 7

Question 25

Question 25:

Evidence preservation is important for fire marshal investigations. Which type of evidence is incorrectly labeled?

A: Physical Evidence: Generally would be any physical or tangible item that tends to prove or disprove a particular fact or issue. At a fire scene, physical evidence may be relevant to the issues of origin, cause, or responsibility. Examples might be incendiary devices, accelerants, trailers, etc..

B: Direct Evidence: Any observation that is pertinent to a point in question and can be legally offered in court. Examples would be the removal of stock prior to the fire or the discovery of an accelerant container not indigenous, etc.

C: Circumstantial Evidence: Something that by itself does not prove a direct fact, but shows that a condition did exist that would lend itself to the occurrence of such an incident.

D: Due to the illusive nature of the crime of arson it is often the accumulation of circumstantial evidence that will become the elements necessary to successfully prosecute a case.

Answer 25

A: Physical Evidence: Generally would be any physical or tangible item that tends to prove or disprove a particular fact or issue. At a fire scene, physical evidence may be relevant to the issues of origin, cause, or responsibility. Examples might be incendiary devices, accelerants, trailers, etc..

B:✔Direct Evidence: Any observation that is pertinent to a point in question and can be legally offered in court. Examples would be the removal of stock prior to the fire or the discovery of an accelerant container not indigenous, etc.

C: Circumstantial Evidence: Something that by itself does not prove a direct fact, but shows that a condition did exist that would lend itself to the occurrence of such an incident.

D: Due to the illusive nature of the crime of arson it is often the accumulation of circumstantial evidence that will become the elements necessary to successfully prosecute a case.

Explanation:
Examples would be the removal of stock prior to the fire or the discovery of an accelerant container not indigenous, is an example of circumstantial evidence
AUC 317 sec 8

Question 26

Question 26:

The ability to recognize and protect physical evidence must be supplemented by a knowledge of the correct procedure in caring for evidence. The continuity of evidence or the chain of custody is the documented trail of evidence from discovery to trial. In order to introduce physical evidence at a trial and insure its evidentiary value. All of the following factors must be considered except:

A: Avoid moving the evidence. If moved during operations make note of location where it was first discovered and notify the fire marshals of these facts upon their arrival. The number of persons who handle the evidence should be kept to a minimum.

B: One person, usually the first ladder officer, must assume responsibility for the evidence. Incident Commanders assuming responsibility of evidence at scenes or removing evidence to quarters must ensure it is secured and protected until the fire marshals arrive.

C: All persons having custody of evidence will become part of this chain and may likely be required to testify as to their actions. Therefore, it is necessary that evidence presented in court be in the condition similar to that in which it was discovered.

D: Contamination is a major concern with potential evidence at a fire scene. Therefore it is imperative that officers and firefighters use common sense and exercise a reasonable degree of care to minimize the possibility of alteration of evidentiary objects. Latent fingerprints are so fragile in nature that a slight act of carelessness in handling can destroy their value.

Answer 26

A: Avoid moving the evidence. If moved during operations make note of location where it was first discovered and notify the fire marshals of these facts upon their arrival. The number of persons who handle the evidence should be kept to a minimum.

B:✔One person, usually the first ladder officer, must assume responsibility for the evidence. Incident Commanders assuming responsibility of evidence at scenes or removing evidence to quarters must ensure it is secured and protected until the fire marshals arrive.

C: All persons having custody of evidence will become part of this chain and may likely be required to testify as to their actions. Therefore, it is necessary that evidence presented in court be in the condition similar to that in which it was discovered.

D: Contamination is a major concern with potential evidence at a fire scene. Therefore it is imperative that officers and firefighters use common sense and exercise a reasonable degree of care to minimize the possibility of alteration of evidentiary objects. Latent fingerprints are so fragile in nature that a slight act of carelessness in handling can destroy their value.

Explanation:
One person, usually the fire marshal
AUC 317 sec 9

Question 27

Question 27:

During drill, members of a Manhattan Ladder Company were discussing how stack effect can impact smoke conditions during a fire operation. Of the following comments made, which was incorrect?

A: Positive Stack Effect occurs in the winter and is when the interior of a building is warmer than the external environment.

B: Negative Stack Effect occurs in the summer and is when the interior of a building is cooler than the external environment.

C: Near the center of the building there will exist an area called the “Stack Effect Neutral Pressure Zone” where air will both be pulled into and pushed out of an opening/floor due to stack effect.

D: Negative Stack Effect, which occurs in the summer, is also known as “Reverse Stack Effect”.

Answer 27

A: Positive Stack Effect occurs in the winter and is when the interior of a building is warmer than the external environment.

B: Negative Stack Effect occurs in the summer and is when the interior of a building is cooler than the external environment.

C:✔Near the center of the building there will exist an area called the “Stack Effect Neutral Pressure Zone” where air will both be pulled into and pushed out of an opening/floor due to stack effect.

D: Negative Stack Effect, which occurs in the summer, is also known as “Reverse Stack Effect”.

Explanation:
C) Near the center of the building there will exist an area that experiences NO horizontal air exchange at all. This area is called the “Stack Effect Neutral Pressure Zone”. In this zone, air will NOT be pulled into or pushed out of an opening or pulled into or pushed out of a floor due to stack effect.
TB FD Ch 4 1.4.1, 1.6.1, 1.7.2 C

Question 28

Question 28:

All firefighters should understand how a “backdraft” occurs. Of the following choices, which is incorrect?

A: A backdraft is a deflagration resulting from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion.

B: During a backdraft, the ignition pushes unburned fuel-rich gases ahead of the burning smoke-air mixture as it expands. A large fire ball results as the burning flammable and smoke-air mixture is forced, under pressure, from the compartment.

C: A backdraft will always lead to a heavy fire condition.

D: Backdraft Indicators include no visible/active flaming within the compartment and extremely limited or no ventilation of the fire compartment.

Answer 28

A: A backdraft is a deflagration resulting from the sudden introduction of air into a confined space containing oxygen-deficient products of incomplete combustion.

B: During a backdraft, the ignition pushes unburned fuel-rich gases ahead of the burning smoke-air mixture as it expands. A large fire ball results as the burning flammable and smoke-air mixture is forced, under pressure, from the compartment.

C:✔A backdraft will always lead to a heavy fire condition.

D: Backdraft Indicators include no visible/active flaming within the compartment and extremely limited or no ventilation of the fire compartment.

Explanation:
C) A backdraft may lead to a heavy fire condition OR may expel all of the fire gases, leaving ONLY LOCALIZED COMBUSTION in its path.
B Note: The over-pressurization and dramatic fireballs produced during backdraft can result in damage to the structure and extension of the fire beyond the compartment, and pose several risks to firefighters who are in its path.
TB FD Ch 3 7.2 - 7.3.2

Question 29

Question 29:

Be able to “read” smoke is a carefully acquired skill. Which of the following choices is incorrect?

A: The volume of smoke may indicate the size, location and stage of the fire within a structure.

B: Smoke velocity is an indicator of pressure that has built up within a structure.

C: Turbulent Smoke indicates extreme heat (closer to the fire).

D: Laminar Smoke indicates high heat or smoke that is close to the fire.

Answer 29

A: The volume of smoke may indicate the size, location and stage of the fire within a structure.

B: Smoke velocity is an indicator of pressure that has built up within a structure.

C: Turbulent Smoke indicates extreme heat (closer to the fire).

D:✔Laminar Smoke indicates high heat or smoke that is close to the fire.

Explanation:
D) Laminar Smoke indicates LOW heat (either because it is a small fire, or the smoke is REMOTE from the fire and has cooled).
A Note: However, the volume of smoke may not always be visible and can be concealed by various building configurations.
B Note: The pressure is developed by buoyancy and expansion due to the amount of heat released by the fire.
C and D Note: Smoke flow can be either laminar (smooth) or turbulent based on the velocity and temperature. Cooler smoke appears to flow smoother. Hotter smoke will appear to boil and move quickly upwards in a turbulent fashion.
TB FD Ch 2 3.5.1, 3.5.2

Question 30

Question 30:

You are completing administrative duties in your office when the proby knocks on the door and enters, asking you to explain what a “boilover” is. You present the proby with correct information in each of the choices below except?

A: A “boilover” is an event in the burning of certain combustible liquids in an open-top tank when, after a long period of quiescent burning, there is a sudden increase in fire intensity associated with the expulsion of burning oil from the tank.

B: When water is added to the fuel, it sinks to the bottom of the container and has little effect on extinguishing the flames which are on the surface of the fuel. Under certain conditions, the water vaporizes into steam causing it to expand more than 1700 times in volume.

C: Boilover commonly occurs in residential kitchen fires when water is added to a grease/oil fire in an attempt to extinguish the fire.

D: In most cases, water will greatly facilitate the extinguishing effect on flaming liquid fires.

Answer 30

A: A “boilover” is an event in the burning of certain combustible liquids in an open-top tank when, after a long period of quiescent burning, there is a sudden increase in fire intensity associated with the expulsion of burning oil from the tank.

B: When water is added to the fuel, it sinks to the bottom of the container and has little effect on extinguishing the flames which are on the surface of the fuel. Under certain conditions, the water vaporizes into steam causing it to expand more than 1700 times in volume.

C: Boilover commonly occurs in residential kitchen fires when water is added to a grease/oil fire in an attempt to extinguish the fire.

D:✔In most cases, water will greatly facilitate the extinguishing effect on flaming liquid fires.

Explanation:
D) In most cases, water (without a suppression additive) has LITTLE EXTINGUISHING EGFECT on flaming liquid fires.
B Note: The rapidly expanding steam expels the fuel upward and out of the container, which ignites and results in a large plume of burning liquid outside of the container.
C Note: Boilover can be more catastrophic when occurring in a larger flammable liquid fire such as a transformer fire or tanker truck fire.
TB FD Ch 3 10.1-10.3