FDNY S-46: SUPERVISION OF STORING,
HANDLING AND USE OF ANHYDROUS
AMMONIA. QUESTIONS AND VERIFIED
ANSWERS JUST RELEASED
1. What is the primary role of the S-46 Certificate of Fitness holder?
A. To design ammonia refrigeration systems.
B. To supervise the storing, handling, and use of anhydrous ammonia.
C. To perform structural repairs on pressure vessels.
D. To authorize the disposal of hazardous waste into public sewers.
Answer: B
Conceptual Explanation: The S-46 COF holder is specifically responsible for the personal
supervision of the storage, handling, and operation of ammonia refrigeration systems.
2. Anhydrous ammonia (NH3) is characterized by which of the following physical properties?
A. Odorless and heavier than air.
B. Sweet smell and extremely flammable.
C. Pungent odor and lighter than air.
D. Greenish gas and corrosive to stainless steel.
,Answer: C
Conceptual Explanation: Ammonia has a sharp, pungent odor and a vapor density of
approximately 0.6, making it lighter than air.
3. What is the IDLH (Immediately Dangerous to Life or Health) level for ammonia according to
NIOSH?
A. 300 ppm
B. 150 ppm
C. 50 ppm
D. 1000 ppm
Answer: A
Conceptual Explanation: The IDLH level for anhydrous ammonia is 300 parts per million
(ppm).
4. Which NFPA 704 diamond rating correctly represents anhydrous ammonia?
A. Health 3, Flammability 1, Instability 0
B. Health 1, Flammability 4, Instability 0
C. Health 2, Flammability 2, Instability 1
D. Health 4, Flammability 0, Instability 2
Answer: A
, Conceptual Explanation: NFPA 704 rates Ammonia as Health 3 (Serious hazard),
Flammability 1 (Slight hazard), and Instability 0 (Minimal hazard).
5. Safety relief valves on ammonia systems must be replaced or recertified every:
A. 1 year
B. 5 years
C. 2 years
D. 10 years
Answer: B
Conceptual Explanation: FDNY and industry standards generally require relief valves to
be replaced or tested/recertified every 5 years to ensure they function during
overpressure.
6. In the event of a significant ammonia leak, what is the first priority of the S-46 COF holder?
A. Ensure the safety of personnel and notify emergency responders.
B. Clean up the spill using water hoses.
C. Restart the compressor to equalize pressure.
D. Close all ventilation louvers immediately.
Answer: A
Conceptual Explanation: Life safety and notification of the FDNY/emergency services are
the absolute priorities in a hazardous material release.
HANDLING AND USE OF ANHYDROUS
AMMONIA. QUESTIONS AND VERIFIED
ANSWERS JUST RELEASED
1. What is the primary role of the S-46 Certificate of Fitness holder?
A. To design ammonia refrigeration systems.
B. To supervise the storing, handling, and use of anhydrous ammonia.
C. To perform structural repairs on pressure vessels.
D. To authorize the disposal of hazardous waste into public sewers.
Answer: B
Conceptual Explanation: The S-46 COF holder is specifically responsible for the personal
supervision of the storage, handling, and operation of ammonia refrigeration systems.
2. Anhydrous ammonia (NH3) is characterized by which of the following physical properties?
A. Odorless and heavier than air.
B. Sweet smell and extremely flammable.
C. Pungent odor and lighter than air.
D. Greenish gas and corrosive to stainless steel.
,Answer: C
Conceptual Explanation: Ammonia has a sharp, pungent odor and a vapor density of
approximately 0.6, making it lighter than air.
3. What is the IDLH (Immediately Dangerous to Life or Health) level for ammonia according to
NIOSH?
A. 300 ppm
B. 150 ppm
C. 50 ppm
D. 1000 ppm
Answer: A
Conceptual Explanation: The IDLH level for anhydrous ammonia is 300 parts per million
(ppm).
4. Which NFPA 704 diamond rating correctly represents anhydrous ammonia?
A. Health 3, Flammability 1, Instability 0
B. Health 1, Flammability 4, Instability 0
C. Health 2, Flammability 2, Instability 1
D. Health 4, Flammability 0, Instability 2
Answer: A
, Conceptual Explanation: NFPA 704 rates Ammonia as Health 3 (Serious hazard),
Flammability 1 (Slight hazard), and Instability 0 (Minimal hazard).
5. Safety relief valves on ammonia systems must be replaced or recertified every:
A. 1 year
B. 5 years
C. 2 years
D. 10 years
Answer: B
Conceptual Explanation: FDNY and industry standards generally require relief valves to
be replaced or tested/recertified every 5 years to ensure they function during
overpressure.
6. In the event of a significant ammonia leak, what is the first priority of the S-46 COF holder?
A. Ensure the safety of personnel and notify emergency responders.
B. Clean up the spill using water hoses.
C. Restart the compressor to equalize pressure.
D. Close all ventilation louvers immediately.
Answer: A
Conceptual Explanation: Life safety and notification of the FDNY/emergency services are
the absolute priorities in a hazardous material release.
