Essential of Fire Fighting 7th edition| & Answers
1. A structure fire in a commercial building involves a large quantity of stored magnesium
shavings. The fire is spreading rapidly, and water application has been ineffective. Which
suppression strategy is most appropriate given the material involved and the fire behavior
observed?
A. Apply a Class B foam blanket to exclude oxygen and cool the metal.
B. Use a dry chemical extinguishing agent rated for Class D fires.
C. Flood the area with water to wash away the shavings and cool the fire.
D. Introduce carbon dioxide (CO2) to create an inert atmosphere.
Answer: B
Rationale: Magnesium is a combustible metal (Class D) that reacts violently with water,
producing hydrogen gas and increasing fire intensity. Class D dry powder agents, such as
sodium chloride or graphite, smother the fire and absorb heat without chemical reaction. Foam
(A) contains water, which is hazardous. Water (C) exacerbates the fire. CO2 (D) can be
ineffective because magnesium can burn in CO2, and the gas may not adequately penetrate the
metal pile.
2. During a hazardous materials incident, a technician uses a photoionization detector
(PID) and a flame ionization detector (FID) simultaneously. The PID shows a reading of 50
ppm, while the FID reads 200 ppm at the same location. What is the most likely
explanation for this discrepancy?
A. The PID is malfunctioning due to high humidity, causing a low reading.
B. The FID is detecting methane, which the PID cannot detect efficiently.
C. The PID is calibrated for a different compound than the one present.
D. The FID is detecting only aromatic hydrocarbons, while the PID detects all VOCs.
Answer: B
Rationale: Photoionization detectors (PIDs) are less sensitive to methane and other
low-molecular-weight hydrocarbons because their ionization potential exceeds the lamp energy.
Flame ionization detectors (FIDs) respond to virtually all hydrocarbons, including methane.
Thus, a high FID reading with a low PID reading suggests the presence of methane or similar
compounds. Option A is less likely because humidity typically affects both instruments. Option C
could cause error but the magnitude of difference is more indicative of methane. Option D is
reversed: FIDs detect all hydrocarbons, while PIDs are selective.
3. A firefighter reports a sharp, stabbing pain in the lower back while lifting a heavy piece
of equipment during overhaul. The pain radiates down the left leg. Which of the following
actions is most appropriate for the company officer to take immediately?
Page 1
,A. Instruct the firefighter to stretch the lower back and continue light duty.
B. Immobilize the firefighter's spine and arrange for immediate medical evaluation.
C. Apply a cold pack to the lower back and administer ibuprofen from the first aid kit.
D. Have the firefighter lie prone and perform a straight leg raise test to confirm nerve involvement.
Answer: B
Rationale: The symptoms (sharp pain, radiating leg pain) suggest a possible herniated disc or
nerve compression, which requires spinal immobilization and prompt medical assessment to
prevent worsening injury. Stretching (A) or applying cold (C) without evaluation could
aggravate the injury. Performing a straight leg raise (D) is a diagnostic maneuver that should
only be done by medical personnel; moving the firefighter could cause further harm.
4. At a structure fire, the incident commander orders the rapid intervention crew (RIC) to
stage at the entry point. The RIC team leader notices that the attack team's hose line has a
kink and the nozzle is closed. The attack team is advancing into a heavily smoke-filled area.
What is the primary hazard the RIC should anticipate?
A. The attack team may become disoriented due to low visibility.
B. The kink may cause a surge in water pressure when opened, injuring firefighters.
C. The attack team may run out of air before reaching the fire.
D. The closed nozzle could lead to a steam burn if the line is suddenly opened near the fire.
Answer: A
Rationale: While all options are potential concerns, the most immediate hazard in a heavy smoke
environment with a kinked hose and closed nozzle is disorientation. The kink reduces water flow,
and the closed nozzle means no water is being applied, so the team may be advancing without a
tactical advantage, increasing the risk of getting lost. Option B is a lesser risk; pressure surges
are typically managed with nozzle control. Option C is possible but not directly related to the
kink/closed nozzle scenario. Option D is a risk but less likely than disorientation in a
zero-visibility environment.
5. A firefighter is trapped under a collapsed ceiling during a structure fire. The rapid
intervention crew (RIC) arrives and finds the firefighter's SCBA facepiece is cracked, and
the PASS device is not sounding. Which of the following actions should the RIC take first?
A. Replace the facepiece with a spare from the RIC's pack.
B. Activate the PASS device manually and begin debris removal.
C. Check the firefighter's air supply and provide breathing air via a universal air connection (UAC).
D. Immediately remove the debris to free the firefighter.
Answer: C
Rationale: The highest priority is to ensure the firefighter has a breathable atmosphere. The
cracked facepiece compromises the SCBA, so providing air via the UAC (if available) or a spare
mask is critical. However, checking the air supply and providing a source of breathing air takes
precedence over PASS activation (B) or debris removal (D), as the firefighter may already be in
respiratory distress. Option A (replacing facepiece) is important but may be secondary if the air
supply is low; providing air through the UAC can be done faster.
Page 2
,6. During a wildland fire suppression operation, a crew is constructing a fireline using hand
tools. The fire behavior is characterized by 15-foot flame lengths and a rate of spread of 5
chains per hour. According to NWCG standards, what is the appropriate crew composition
and tactical approach?
A. A 20-person hand crew with direct attack using hand tools and water.
B. A 5-person initial attack crew with a Type 6 engine and direct attack.
C. A 10-person hand crew with indirect attack using burnout operations.
D. A 15-person crew with aerial support for retardant drops before ground attack.
Answer: C
Rationale: Flame lengths of 15 feet indicate extreme fire behavior, making direct attack unsafe.
Indirect attack with burnout operations is appropriate. A 10-person hand crew is standard for
such conditions. Option A (20-person) might be used for larger fires but direct attack is not
recommended. Option B (5-person) is too small for extreme behavior. Option D (aerial support)
could be used but ground crew size and indirect attack are more specific to the scenario.
7. A fire department responds to a reported leak of anhydrous ammonia from a
refrigeration unit at an ice rink. The wind is blowing from the north at 10 mph. The leak is
located at the south end of the building. Which of the following actions should be taken
first?
A. Evacuate all civilians to the north side of the building.
B. Approach from the south to access the leak source.
C. Use water fog to knock down the vapor cloud.
D. Isolate the area and deny entry from all directions.
Answer: A
Rationale: Anhydrous ammonia is toxic and lighter than air. With a north wind, the vapor will
spread southward. Evacuating to the north (upwind) is the priority to protect lives. Approaching
from the south (B) would be downwind and dangerous. Water fog (C) can be used to disperse
ammonia vapor but should not be the first action before evacuation. Denying entry (D) is
important but evacuation of those in the immediate hazard zone takes precedence.
8. A firefighter is performing salvage operations on the floor below a fire. The ceiling above
begins to show signs of water accumulation, and a bulge appears. Which of the following is
the most appropriate action?
A. Poke a small hole in the center of the bulge to drain the water into a salvage container.
B. Use a ceiling hook to pull down the ceiling material in a controlled manner.
C. Immediately evacuate the area due to risk of ceiling collapse.
D. Place a salvage cover over the floor and continue operations.
Answer: A
Rationale: The bulge indicates water pooling above, which can cause ceiling collapse. Poking a
small hole allows controlled drainage, reducing weight and preventing sudden collapse. Option
B (pulling down the entire section) could cause a large amount of water to fall suddenly,
increasing risk. Option C (evacuation) is unnecessary if water can be drained safely. Option D
Page 3
, (placing a cover) does not address the immediate hazard of the bulging ceiling.
9. A fire company is called to a motor vehicle collision involving a tanker truck carrying
liquefied petroleum gas (LPG). The tanker is upright with a small leak from a valve. There
is no fire. The driver is trapped in the cab. What is the most appropriate initial strategy?
A. Extricate the driver immediately using hydraulic tools.
B. Set up a defensive perimeter and allow the LPG to dissipate.
C. Use a water spray to cool the tank and dilute the leak.
D. Close the leaking valve if possible and then proceed with extrication.
Answer: D
Rationale: LPG is highly flammable and can form explosive mixtures. The priority is to stop the
leak to reduce the hazard. If the valve can be closed safely (e.g., from a distance with a
long-handled tool), that should be done first. Extrication (A) without leak control risks ignition.
Defensive perimeter (B) is too passive and delays rescue. Water spray (C) can be used to cool
but does not stop the leak; it may also spread the vapor.
10. During a fire in a high-rise building, the incident commander orders the use of the
building's standpipe system. The attack team connects to a standpipe outlet on the 15th
floor. The fire is on the 20th floor. The pump operator at the street level is supplying the
standpipe with a pressure of 150 psi. What is the approximate pressure available at the
15th floor outlet, assuming a static pressure loss of 5 psi per floor?
A. 75 psi
B. 100 psi
C. 125 psi
D. 150 psi
Answer: A
Rationale: Static pressure loss in standpipes is typically estimated at 5 psi per floor due to
elevation. From the street (floor 0) to the 15th floor, the loss is 15 floors × 5 psi/floor = 75 psi.
Thus, pressure at the 15th floor outlet = 150 psi - 75 psi = 75 psi. This is the static pressure;
when flowing, additional friction losses will reduce it further. Option B (100 psi) assumes 10
floors loss; C (125 psi) assumes 5 floors loss; D (150 psi) ignores elevation loss.
11. During a structure fire, a firefighter notices that the fire is transitioning from a
fuel-limited to a ventilation-limited phase. Which of the following tactical considerations is
MOST critical for crew safety at this stage?
A. Increasing the flow rate of the attack line to cool the upper gas layer
B. Coordinating ventilation with suppression to avoid rapid fire progression
C. Withdrawing immediately due to potential backdraft conditions
D. Applying a straight stream directly to the seat of the fire
Answer: B
Page 4
1. A structure fire in a commercial building involves a large quantity of stored magnesium
shavings. The fire is spreading rapidly, and water application has been ineffective. Which
suppression strategy is most appropriate given the material involved and the fire behavior
observed?
A. Apply a Class B foam blanket to exclude oxygen and cool the metal.
B. Use a dry chemical extinguishing agent rated for Class D fires.
C. Flood the area with water to wash away the shavings and cool the fire.
D. Introduce carbon dioxide (CO2) to create an inert atmosphere.
Answer: B
Rationale: Magnesium is a combustible metal (Class D) that reacts violently with water,
producing hydrogen gas and increasing fire intensity. Class D dry powder agents, such as
sodium chloride or graphite, smother the fire and absorb heat without chemical reaction. Foam
(A) contains water, which is hazardous. Water (C) exacerbates the fire. CO2 (D) can be
ineffective because magnesium can burn in CO2, and the gas may not adequately penetrate the
metal pile.
2. During a hazardous materials incident, a technician uses a photoionization detector
(PID) and a flame ionization detector (FID) simultaneously. The PID shows a reading of 50
ppm, while the FID reads 200 ppm at the same location. What is the most likely
explanation for this discrepancy?
A. The PID is malfunctioning due to high humidity, causing a low reading.
B. The FID is detecting methane, which the PID cannot detect efficiently.
C. The PID is calibrated for a different compound than the one present.
D. The FID is detecting only aromatic hydrocarbons, while the PID detects all VOCs.
Answer: B
Rationale: Photoionization detectors (PIDs) are less sensitive to methane and other
low-molecular-weight hydrocarbons because their ionization potential exceeds the lamp energy.
Flame ionization detectors (FIDs) respond to virtually all hydrocarbons, including methane.
Thus, a high FID reading with a low PID reading suggests the presence of methane or similar
compounds. Option A is less likely because humidity typically affects both instruments. Option C
could cause error but the magnitude of difference is more indicative of methane. Option D is
reversed: FIDs detect all hydrocarbons, while PIDs are selective.
3. A firefighter reports a sharp, stabbing pain in the lower back while lifting a heavy piece
of equipment during overhaul. The pain radiates down the left leg. Which of the following
actions is most appropriate for the company officer to take immediately?
Page 1
,A. Instruct the firefighter to stretch the lower back and continue light duty.
B. Immobilize the firefighter's spine and arrange for immediate medical evaluation.
C. Apply a cold pack to the lower back and administer ibuprofen from the first aid kit.
D. Have the firefighter lie prone and perform a straight leg raise test to confirm nerve involvement.
Answer: B
Rationale: The symptoms (sharp pain, radiating leg pain) suggest a possible herniated disc or
nerve compression, which requires spinal immobilization and prompt medical assessment to
prevent worsening injury. Stretching (A) or applying cold (C) without evaluation could
aggravate the injury. Performing a straight leg raise (D) is a diagnostic maneuver that should
only be done by medical personnel; moving the firefighter could cause further harm.
4. At a structure fire, the incident commander orders the rapid intervention crew (RIC) to
stage at the entry point. The RIC team leader notices that the attack team's hose line has a
kink and the nozzle is closed. The attack team is advancing into a heavily smoke-filled area.
What is the primary hazard the RIC should anticipate?
A. The attack team may become disoriented due to low visibility.
B. The kink may cause a surge in water pressure when opened, injuring firefighters.
C. The attack team may run out of air before reaching the fire.
D. The closed nozzle could lead to a steam burn if the line is suddenly opened near the fire.
Answer: A
Rationale: While all options are potential concerns, the most immediate hazard in a heavy smoke
environment with a kinked hose and closed nozzle is disorientation. The kink reduces water flow,
and the closed nozzle means no water is being applied, so the team may be advancing without a
tactical advantage, increasing the risk of getting lost. Option B is a lesser risk; pressure surges
are typically managed with nozzle control. Option C is possible but not directly related to the
kink/closed nozzle scenario. Option D is a risk but less likely than disorientation in a
zero-visibility environment.
5. A firefighter is trapped under a collapsed ceiling during a structure fire. The rapid
intervention crew (RIC) arrives and finds the firefighter's SCBA facepiece is cracked, and
the PASS device is not sounding. Which of the following actions should the RIC take first?
A. Replace the facepiece with a spare from the RIC's pack.
B. Activate the PASS device manually and begin debris removal.
C. Check the firefighter's air supply and provide breathing air via a universal air connection (UAC).
D. Immediately remove the debris to free the firefighter.
Answer: C
Rationale: The highest priority is to ensure the firefighter has a breathable atmosphere. The
cracked facepiece compromises the SCBA, so providing air via the UAC (if available) or a spare
mask is critical. However, checking the air supply and providing a source of breathing air takes
precedence over PASS activation (B) or debris removal (D), as the firefighter may already be in
respiratory distress. Option A (replacing facepiece) is important but may be secondary if the air
supply is low; providing air through the UAC can be done faster.
Page 2
,6. During a wildland fire suppression operation, a crew is constructing a fireline using hand
tools. The fire behavior is characterized by 15-foot flame lengths and a rate of spread of 5
chains per hour. According to NWCG standards, what is the appropriate crew composition
and tactical approach?
A. A 20-person hand crew with direct attack using hand tools and water.
B. A 5-person initial attack crew with a Type 6 engine and direct attack.
C. A 10-person hand crew with indirect attack using burnout operations.
D. A 15-person crew with aerial support for retardant drops before ground attack.
Answer: C
Rationale: Flame lengths of 15 feet indicate extreme fire behavior, making direct attack unsafe.
Indirect attack with burnout operations is appropriate. A 10-person hand crew is standard for
such conditions. Option A (20-person) might be used for larger fires but direct attack is not
recommended. Option B (5-person) is too small for extreme behavior. Option D (aerial support)
could be used but ground crew size and indirect attack are more specific to the scenario.
7. A fire department responds to a reported leak of anhydrous ammonia from a
refrigeration unit at an ice rink. The wind is blowing from the north at 10 mph. The leak is
located at the south end of the building. Which of the following actions should be taken
first?
A. Evacuate all civilians to the north side of the building.
B. Approach from the south to access the leak source.
C. Use water fog to knock down the vapor cloud.
D. Isolate the area and deny entry from all directions.
Answer: A
Rationale: Anhydrous ammonia is toxic and lighter than air. With a north wind, the vapor will
spread southward. Evacuating to the north (upwind) is the priority to protect lives. Approaching
from the south (B) would be downwind and dangerous. Water fog (C) can be used to disperse
ammonia vapor but should not be the first action before evacuation. Denying entry (D) is
important but evacuation of those in the immediate hazard zone takes precedence.
8. A firefighter is performing salvage operations on the floor below a fire. The ceiling above
begins to show signs of water accumulation, and a bulge appears. Which of the following is
the most appropriate action?
A. Poke a small hole in the center of the bulge to drain the water into a salvage container.
B. Use a ceiling hook to pull down the ceiling material in a controlled manner.
C. Immediately evacuate the area due to risk of ceiling collapse.
D. Place a salvage cover over the floor and continue operations.
Answer: A
Rationale: The bulge indicates water pooling above, which can cause ceiling collapse. Poking a
small hole allows controlled drainage, reducing weight and preventing sudden collapse. Option
B (pulling down the entire section) could cause a large amount of water to fall suddenly,
increasing risk. Option C (evacuation) is unnecessary if water can be drained safely. Option D
Page 3
, (placing a cover) does not address the immediate hazard of the bulging ceiling.
9. A fire company is called to a motor vehicle collision involving a tanker truck carrying
liquefied petroleum gas (LPG). The tanker is upright with a small leak from a valve. There
is no fire. The driver is trapped in the cab. What is the most appropriate initial strategy?
A. Extricate the driver immediately using hydraulic tools.
B. Set up a defensive perimeter and allow the LPG to dissipate.
C. Use a water spray to cool the tank and dilute the leak.
D. Close the leaking valve if possible and then proceed with extrication.
Answer: D
Rationale: LPG is highly flammable and can form explosive mixtures. The priority is to stop the
leak to reduce the hazard. If the valve can be closed safely (e.g., from a distance with a
long-handled tool), that should be done first. Extrication (A) without leak control risks ignition.
Defensive perimeter (B) is too passive and delays rescue. Water spray (C) can be used to cool
but does not stop the leak; it may also spread the vapor.
10. During a fire in a high-rise building, the incident commander orders the use of the
building's standpipe system. The attack team connects to a standpipe outlet on the 15th
floor. The fire is on the 20th floor. The pump operator at the street level is supplying the
standpipe with a pressure of 150 psi. What is the approximate pressure available at the
15th floor outlet, assuming a static pressure loss of 5 psi per floor?
A. 75 psi
B. 100 psi
C. 125 psi
D. 150 psi
Answer: A
Rationale: Static pressure loss in standpipes is typically estimated at 5 psi per floor due to
elevation. From the street (floor 0) to the 15th floor, the loss is 15 floors × 5 psi/floor = 75 psi.
Thus, pressure at the 15th floor outlet = 150 psi - 75 psi = 75 psi. This is the static pressure;
when flowing, additional friction losses will reduce it further. Option B (100 psi) assumes 10
floors loss; C (125 psi) assumes 5 floors loss; D (150 psi) ignores elevation loss.
11. During a structure fire, a firefighter notices that the fire is transitioning from a
fuel-limited to a ventilation-limited phase. Which of the following tactical considerations is
MOST critical for crew safety at this stage?
A. Increasing the flow rate of the attack line to cool the upper gas layer
B. Coordinating ventilation with suppression to avoid rapid fire progression
C. Withdrawing immediately due to potential backdraft conditions
D. Applying a straight stream directly to the seat of the fire
Answer: B
Page 4
