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Z-51 WRITTEN TEST EXAM (LATEST UPDATE 2026)
UPDATE!! (RECENT EXAM) FULLY SOLVED & UPDATED
2026 MOST TESTED (2026
In a steam turbine, what is the function of a Kingsbury thrust bearing?
A) Maintain first stage steam pressure.
B) Compensate for coupling misalignment.
C) Adjust shaft torque at start up.
D) Maintain axial positioning of the rotor shaft. ......ANSWER......D)
Maintain axial positioning of the rotor shaft.
When must the Fire Department be notified that a fire protection
system is out of service?
A) The manual pull alarm station in the lobby will be out of service for 4
hours.
B) Four sprinkler heads on a same floor of your building will be out of
service for 2 hours.
C) The sprinkler system will be out of service on 1st and 2nd floors.
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D) The fire alarm system is out of service in the refrigerating system
room for g hours. ......ANSWER......C) The sprinkler system will be out of
service on 1st and 2nd floors.
Hot work authorizations are issued by
A) a Responsible Person designated by the Building Owner.
B) a Building Department inspector.
C) a FDNY inspector.
D) the Building owner's insurance company. ......ANSWER......A) a
Responsible Person designated by the building owner.
Insecticidal fogging operations are hazardous because chemicals
A) are corrosive.
B) are water-reactive.
C) may be toxic.
D) are highly unstable. ......ANSWER......C) may be toxic.
Where is emergency power not required according to code?
A) Fire pumps.
B) High rise elevators.
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C) Egress illumination.
D) Data centers. ......ANSWER......D) Data centers.
Modern compressors usually seal the rotating shaft seal as it exits the
compressor housing a spring-loaded seal made of
A) low-friction plastic.
B) rubber.
C) metal or carbon.
D) graphite-loaded fiber. ......ANSWER......
A technician shows up to service the fire alarm panel in your building.
What COF qualifications must he/she have?
A) A Q-01/Q-99 Certificate of Qualification holder who is designated by
the building owner.
B) A certified Fire Safety Director who is designated by the building
owner.
C) A S-95 Certificate of Fitness holder who is employed by a FDNY
certified company.
D) A S-97/S-98 Certificate of Fitness holder who is employed by a FDNY
certified company. ......ANSWER......D) A S-97/S-98 Certificate of Fitness
holder who is employed by a FDNY certified company.
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In an office building, the display of cut natural trees (Christmas trees) is
A) never allowed.
B) allowed provided they are removed once they dry out.
C) always allowed.
D) allowed during the holiday season. ......ANSWER......A) never allowed.
Describe the equipment's function in the picture.
A) Control flow of refrigerant to the compressor.
B) Remove non-condensable from the condenser.
C) Relieve excess pressure from the condenser.
D) Relieve excess pressure from the evaporator. ......ANSWER......B)
Remove non-condensable from the condenser.
When the expansion valve is operating properly, the end of the
evaporator will contain
A) only superheated vapor.
B) saturated liquid refrigerant
C) only vapor.
D) only liquid refrigerant. ......ANSWER......A) only superheated vapor.
Z-51 WRITTEN TEST EXAM (LATEST UPDATE 2026)
UPDATE!! (RECENT EXAM) FULLY SOLVED & UPDATED
2026 MOST TESTED (2026
In a steam turbine, what is the function of a Kingsbury thrust bearing?
A) Maintain first stage steam pressure.
B) Compensate for coupling misalignment.
C) Adjust shaft torque at start up.
D) Maintain axial positioning of the rotor shaft. ......ANSWER......D)
Maintain axial positioning of the rotor shaft.
When must the Fire Department be notified that a fire protection
system is out of service?
A) The manual pull alarm station in the lobby will be out of service for 4
hours.
B) Four sprinkler heads on a same floor of your building will be out of
service for 2 hours.
C) The sprinkler system will be out of service on 1st and 2nd floors.
,2|Page
D) The fire alarm system is out of service in the refrigerating system
room for g hours. ......ANSWER......C) The sprinkler system will be out of
service on 1st and 2nd floors.
Hot work authorizations are issued by
A) a Responsible Person designated by the Building Owner.
B) a Building Department inspector.
C) a FDNY inspector.
D) the Building owner's insurance company. ......ANSWER......A) a
Responsible Person designated by the building owner.
Insecticidal fogging operations are hazardous because chemicals
A) are corrosive.
B) are water-reactive.
C) may be toxic.
D) are highly unstable. ......ANSWER......C) may be toxic.
Where is emergency power not required according to code?
A) Fire pumps.
B) High rise elevators.
,3|Page
C) Egress illumination.
D) Data centers. ......ANSWER......D) Data centers.
Modern compressors usually seal the rotating shaft seal as it exits the
compressor housing a spring-loaded seal made of
A) low-friction plastic.
B) rubber.
C) metal or carbon.
D) graphite-loaded fiber. ......ANSWER......
A technician shows up to service the fire alarm panel in your building.
What COF qualifications must he/she have?
A) A Q-01/Q-99 Certificate of Qualification holder who is designated by
the building owner.
B) A certified Fire Safety Director who is designated by the building
owner.
C) A S-95 Certificate of Fitness holder who is employed by a FDNY
certified company.
D) A S-97/S-98 Certificate of Fitness holder who is employed by a FDNY
certified company. ......ANSWER......D) A S-97/S-98 Certificate of Fitness
holder who is employed by a FDNY certified company.
, 4|Page
In an office building, the display of cut natural trees (Christmas trees) is
A) never allowed.
B) allowed provided they are removed once they dry out.
C) always allowed.
D) allowed during the holiday season. ......ANSWER......A) never allowed.
Describe the equipment's function in the picture.
A) Control flow of refrigerant to the compressor.
B) Remove non-condensable from the condenser.
C) Relieve excess pressure from the condenser.
D) Relieve excess pressure from the evaporator. ......ANSWER......B)
Remove non-condensable from the condenser.
When the expansion valve is operating properly, the end of the
evaporator will contain
A) only superheated vapor.
B) saturated liquid refrigerant
C) only vapor.
D) only liquid refrigerant. ......ANSWER......A) only superheated vapor.
