FDNY C-92 DIESEL FUEL OIL TRANSFER
Questions And Correct Answers With
Rationales
Practice Question Bank & Answer Rationale
THIS PACK CONTAINS
150 exam-style multiple-choice questions. Each question includes the correct answer and a complete
rationale for focused revision.
COVERAGE
This exam assesses competency in the safe transfer, storage, and handling of diesel fuel oil under FDNY
C-92 Certificate of Fitness standards. It covers fuel properties, transfer system components, regulatory
requirements, spill prevention, emergency procedures, and inspection/maintenance practices for facilities
operating diesel fuel oil transfer systems in New York City.
STUDY GUIDE
Recommended duration: 2 hours. Passing target: 70%.
HIGHP - Page 1 of 48
,1. Which of the following best describes the primary safety concern when transferring
diesel fuel oil with a flash point of approximately 140°F (60°C)?
[ ] A. The fuel will ignite at ambient temperatures above 100°F.
[ ] B. The fuel produces flammable vapors that can travel to an ignition source at room temperature.
[ ] C. The fuel must be heated above its flash point before it can burn, requiring a sustained ignition
source.
[ ] D. The fuel is classified as a flammable liquid under NFPA 30 and requires explosion-proof
equipment.
CORRECT: C. The fuel must be heated above its flash point before it can burn, requiring a sustained
ignition source.
Diesel fuel oil with a flash point of 140°F is classified as a combustible liquid (Class II), not a flammable liquid.
It requires heating above its flash point to produce ignitable vapors, so a sustained ignition source is typically
needed. Options A, B, and D incorrectly suggest it behaves like a flammable liquid with vapors ignitable at
room temperature.
2. During a routine inspection of a diesel fuel oil transfer system, you notice the piping is
labeled with a yellow band. According to FDNY and industry standards, what does this
color coding indicate?
[ ] A. The piping contains flammable liquids.
[ ] B. The piping contains combustible liquids.
[ ] C. The piping contains compressed air.
[ ] D. The piping contains potable water.
CORRECT: B. The piping contains combustible liquids.
Yellow is the standard color code for combustible liquids, such as diesel fuel oil, under NFPA and FDNY
guidelines. Flammable liquids are typically red, compressed air is often blue, and potable water is green. This
color coding helps prevent cross-connection errors during transfer operations.
3. A facility stores diesel fuel oil in an aboveground tank. Which of the following is a
required secondary containment measure under FDNY C-92 regulations?
[ ] A. A concrete dike around the tank with a capacity of at least 110% of the tank volume.
[ ] B. A double-walled tank with interstitial monitoring.
[ ] C. A remote shutoff valve located 50 feet from the tank.
[ ] D. A foam fire suppression system installed within 10 feet of the tank.
CORRECT: A. A concrete dike around the tank with a capacity of at least 110% of the tank volume.
FDNY C-92 requires secondary containment for aboveground storage tanks, typically a dike or berm capable
of holding at least 110% of the tank's volume to contain spills or leaks. Double-walled tanks are an alternative
but not the only required method. Remote shutoff valves and foam systems are separate safety features, not
secondary containment.
HIGHP - Page 2 of 48
,4. Which document must be readily available at a facility that transfers diesel fuel oil and
is subject to FDNY C-92?
[ ] A. A current certificate of fitness for the person supervising the transfer.
[ ] B. A notarized letter from the fuel supplier.
[ ] C. A monthly water quality report.
[ ] D. A fire evacuation plan for the surrounding neighborhood.
CORRECT: A. A current certificate of fitness for the person supervising the transfer.
FDNY C-92 requires that a person holding a valid Certificate of Fitness be present during fuel oil transfer
operations, and the certificate must be available for inspection. Other documents like supplier letters or water
reports are not mandated by C-92. The fire evacuation plan is required under other codes but not specifically
for fuel transfer.
5. When transferring diesel fuel oil from a tank truck to an aboveground storage tank,
which practice helps prevent static electricity ignition?
[ ] A. Increasing the flow rate to minimize transfer time.
[ ] B. Bonding the truck to the storage tank and grounding both.
[ ] C. Using plastic hoses to insulate the transfer line.
[ ] D. Transferring fuel only during daylight hours.
CORRECT: B. Bonding the truck to the storage tank and grounding both.
Bonding and grounding equalize electrical potential between the truck and tank, preventing static sparks that
can ignite fuel vapors. Increasing flow rate generates more static, plastic hoses do not dissipate static, and
time of day does not affect static buildup. This is a standard safety practice in fuel transfer operations.
6. A diesel fuel oil transfer system is equipped with a backflow preventer. What is the
primary purpose of this device?
[ ] A. To prevent fuel from flowing back into the supply source and contaminating it.
[ ] B. To increase the pressure of the fuel during transfer.
[ ] C. To filter out particulate matter from the fuel.
[ ] D. To measure the volume of fuel transferred.
CORRECT: A. To prevent fuel from flowing back into the supply source and contaminating it.
A backflow preventer ensures that fuel flows in only one direction, preventing contamination of the supply
source or cross-connection with other systems. It does not increase pressure, filter fuel, or measure volume.
These functions are handled by pumps, filters, and meters, respectively.
7. Which of the following is a key step in the emergency shutdown procedure for a diesel
fuel oil transfer operation upon detecting a leak?
[ ] A. Immediately activate the emergency stop button to halt the pump.
HIGHP - Page 3 of 48
, [ ] B. Continue the transfer to empty the hose and then stop.
[ ] C. Notify the fuel supplier before taking any action.
[ ] D. Open all valves to relieve pressure in the system.
CORRECT: A. Immediately activate the emergency stop button to halt the pump.
The first action in a leak emergency is to stop the transfer immediately by activating the emergency stop,
which halts the pump and isolates the flow. Continuing transfer or opening valves would worsen the spill.
Notifying the supplier is important but secondary to stopping the leak.
8. What is the minimum required separation distance between an aboveground diesel fuel
oil storage tank and a property line, according to typical FDNY C-92 and NFPA 30
requirements for tanks with capacities over 1,000 gallons?
[ ] A. 5 feet
[ ] B. 10 feet
[ ] C. 25 feet
[ ] D. 50 feet
CORRECT: B. 10 feet
NFPA 30 and FDNY C-92 generally require a minimum separation of 10 feet between aboveground
combustible liquid storage tanks over 1,000 gallons and a property line. Smaller tanks may have lesser
requirements, while larger or flammable liquid tanks require greater distances. 5 feet is too close, and 25 or
50 feet exceed the standard requirement.
9. A fuel oil transfer system uses a centrifugal pump. Which of the following conditions
could cause cavitation and reduced transfer efficiency?
[ ] A. Excessive suction lift or a clogged suction strainer.
[ ] B. A fully open discharge valve.
[ ] C. A high fuel temperature above 100°F.
[ ] D. A properly primed pump casing.
CORRECT: A. Excessive suction lift or a clogged suction strainer.
Cavitation occurs when the pump suction pressure drops below the vapor pressure of the fuel, often due to
excessive suction lift or a clogged strainer, causing vapor bubbles that collapse and damage the pump. A
fully open discharge valve, high fuel temperature (within limits), and proper priming do not cause cavitation.
Maintaining proper net positive suction head (NPSH) prevents this condition.
10. Which of the following best describes the required action when a spill of diesel fuel oil
exceeds 25 gallons during a transfer operation in New York City?
[ ] A. Report the spill to the FDNY and NYSDEC immediately, and begin cleanup using appropriate
absorbents.
HIGHP - Page 4 of 48
Questions And Correct Answers With
Rationales
Practice Question Bank & Answer Rationale
THIS PACK CONTAINS
150 exam-style multiple-choice questions. Each question includes the correct answer and a complete
rationale for focused revision.
COVERAGE
This exam assesses competency in the safe transfer, storage, and handling of diesel fuel oil under FDNY
C-92 Certificate of Fitness standards. It covers fuel properties, transfer system components, regulatory
requirements, spill prevention, emergency procedures, and inspection/maintenance practices for facilities
operating diesel fuel oil transfer systems in New York City.
STUDY GUIDE
Recommended duration: 2 hours. Passing target: 70%.
HIGHP - Page 1 of 48
,1. Which of the following best describes the primary safety concern when transferring
diesel fuel oil with a flash point of approximately 140°F (60°C)?
[ ] A. The fuel will ignite at ambient temperatures above 100°F.
[ ] B. The fuel produces flammable vapors that can travel to an ignition source at room temperature.
[ ] C. The fuel must be heated above its flash point before it can burn, requiring a sustained ignition
source.
[ ] D. The fuel is classified as a flammable liquid under NFPA 30 and requires explosion-proof
equipment.
CORRECT: C. The fuel must be heated above its flash point before it can burn, requiring a sustained
ignition source.
Diesel fuel oil with a flash point of 140°F is classified as a combustible liquid (Class II), not a flammable liquid.
It requires heating above its flash point to produce ignitable vapors, so a sustained ignition source is typically
needed. Options A, B, and D incorrectly suggest it behaves like a flammable liquid with vapors ignitable at
room temperature.
2. During a routine inspection of a diesel fuel oil transfer system, you notice the piping is
labeled with a yellow band. According to FDNY and industry standards, what does this
color coding indicate?
[ ] A. The piping contains flammable liquids.
[ ] B. The piping contains combustible liquids.
[ ] C. The piping contains compressed air.
[ ] D. The piping contains potable water.
CORRECT: B. The piping contains combustible liquids.
Yellow is the standard color code for combustible liquids, such as diesel fuel oil, under NFPA and FDNY
guidelines. Flammable liquids are typically red, compressed air is often blue, and potable water is green. This
color coding helps prevent cross-connection errors during transfer operations.
3. A facility stores diesel fuel oil in an aboveground tank. Which of the following is a
required secondary containment measure under FDNY C-92 regulations?
[ ] A. A concrete dike around the tank with a capacity of at least 110% of the tank volume.
[ ] B. A double-walled tank with interstitial monitoring.
[ ] C. A remote shutoff valve located 50 feet from the tank.
[ ] D. A foam fire suppression system installed within 10 feet of the tank.
CORRECT: A. A concrete dike around the tank with a capacity of at least 110% of the tank volume.
FDNY C-92 requires secondary containment for aboveground storage tanks, typically a dike or berm capable
of holding at least 110% of the tank's volume to contain spills or leaks. Double-walled tanks are an alternative
but not the only required method. Remote shutoff valves and foam systems are separate safety features, not
secondary containment.
HIGHP - Page 2 of 48
,4. Which document must be readily available at a facility that transfers diesel fuel oil and
is subject to FDNY C-92?
[ ] A. A current certificate of fitness for the person supervising the transfer.
[ ] B. A notarized letter from the fuel supplier.
[ ] C. A monthly water quality report.
[ ] D. A fire evacuation plan for the surrounding neighborhood.
CORRECT: A. A current certificate of fitness for the person supervising the transfer.
FDNY C-92 requires that a person holding a valid Certificate of Fitness be present during fuel oil transfer
operations, and the certificate must be available for inspection. Other documents like supplier letters or water
reports are not mandated by C-92. The fire evacuation plan is required under other codes but not specifically
for fuel transfer.
5. When transferring diesel fuel oil from a tank truck to an aboveground storage tank,
which practice helps prevent static electricity ignition?
[ ] A. Increasing the flow rate to minimize transfer time.
[ ] B. Bonding the truck to the storage tank and grounding both.
[ ] C. Using plastic hoses to insulate the transfer line.
[ ] D. Transferring fuel only during daylight hours.
CORRECT: B. Bonding the truck to the storage tank and grounding both.
Bonding and grounding equalize electrical potential between the truck and tank, preventing static sparks that
can ignite fuel vapors. Increasing flow rate generates more static, plastic hoses do not dissipate static, and
time of day does not affect static buildup. This is a standard safety practice in fuel transfer operations.
6. A diesel fuel oil transfer system is equipped with a backflow preventer. What is the
primary purpose of this device?
[ ] A. To prevent fuel from flowing back into the supply source and contaminating it.
[ ] B. To increase the pressure of the fuel during transfer.
[ ] C. To filter out particulate matter from the fuel.
[ ] D. To measure the volume of fuel transferred.
CORRECT: A. To prevent fuel from flowing back into the supply source and contaminating it.
A backflow preventer ensures that fuel flows in only one direction, preventing contamination of the supply
source or cross-connection with other systems. It does not increase pressure, filter fuel, or measure volume.
These functions are handled by pumps, filters, and meters, respectively.
7. Which of the following is a key step in the emergency shutdown procedure for a diesel
fuel oil transfer operation upon detecting a leak?
[ ] A. Immediately activate the emergency stop button to halt the pump.
HIGHP - Page 3 of 48
, [ ] B. Continue the transfer to empty the hose and then stop.
[ ] C. Notify the fuel supplier before taking any action.
[ ] D. Open all valves to relieve pressure in the system.
CORRECT: A. Immediately activate the emergency stop button to halt the pump.
The first action in a leak emergency is to stop the transfer immediately by activating the emergency stop,
which halts the pump and isolates the flow. Continuing transfer or opening valves would worsen the spill.
Notifying the supplier is important but secondary to stopping the leak.
8. What is the minimum required separation distance between an aboveground diesel fuel
oil storage tank and a property line, according to typical FDNY C-92 and NFPA 30
requirements for tanks with capacities over 1,000 gallons?
[ ] A. 5 feet
[ ] B. 10 feet
[ ] C. 25 feet
[ ] D. 50 feet
CORRECT: B. 10 feet
NFPA 30 and FDNY C-92 generally require a minimum separation of 10 feet between aboveground
combustible liquid storage tanks over 1,000 gallons and a property line. Smaller tanks may have lesser
requirements, while larger or flammable liquid tanks require greater distances. 5 feet is too close, and 25 or
50 feet exceed the standard requirement.
9. A fuel oil transfer system uses a centrifugal pump. Which of the following conditions
could cause cavitation and reduced transfer efficiency?
[ ] A. Excessive suction lift or a clogged suction strainer.
[ ] B. A fully open discharge valve.
[ ] C. A high fuel temperature above 100°F.
[ ] D. A properly primed pump casing.
CORRECT: A. Excessive suction lift or a clogged suction strainer.
Cavitation occurs when the pump suction pressure drops below the vapor pressure of the fuel, often due to
excessive suction lift or a clogged strainer, causing vapor bubbles that collapse and damage the pump. A
fully open discharge valve, high fuel temperature (within limits), and proper priming do not cause cavitation.
Maintaining proper net positive suction head (NPSH) prevents this condition.
10. Which of the following best describes the required action when a spill of diesel fuel oil
exceeds 25 gallons during a transfer operation in New York City?
[ ] A. Report the spill to the FDNY and NYSDEC immediately, and begin cleanup using appropriate
absorbents.
HIGHP - Page 4 of 48
