Practice Examination Questions And Correct

FDNY Certificate of Fitness A-35: To Operate

and Maintain Air Compressors Practice Examination Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

1.What is the primary function of an air compressor in building operations?

• Increase electrical efficiency
• Remove heat from mechanical rooms
• Supply compressed air for equipment and systems
• Regulate water pressure

Rationale: Compressors are designed to pressurize air for use in tools,

controls, and building systems.

2.Air receivers are required to have which safety device?

• Electrical interlock
• ASME-rated pressure relief valve 1 / 4

• Evacuation buzzer
• Water mist detector

Rationale: Relief valves prevent over-pressurization and are required on all

air receivers.

3.Which gauge indicates the pressure inside the compressor discharge line?

• Vacuum gauge
• Pressure gauge
• Temperature gauge
• Flow meter

Rationale: Pressure gauges show air pressure within the compressor and

discharge piping.

4.Which lubrication method is common for reciprocating compressors?

• Dry chemical feed
• Splash or force-feed lubrication
• Vapor lubrication
• Hydraulic loop

Rationale: Reciprocating compressors rely on splash or force-feed oil

lubrication for moving parts.

5. 2 / 4

What is a major hazard associated with compressed air?

• Excessive humidity
• Increased air circulation
• Stored energy capable of violent release
• Dust buildup

Rationale: Compressed air contains stored energy, which can cause

explosions or equipment damage.

6.What must be done before servicing or repairing an air compressor?

• Reduce humidity
• Close all room doors
• Lockout and tagout the power supply
• Add coolant

Rationale: Lockout/tagout prevents unexpected startup during service.

7.What is the purpose of an intercooler in a multi-stage compressor?

• Increase noise
• Add moisture
• Reduce temperature between stages
• Reduce pressure

Rationale: Intercoolers cool compressed air to improve efficiency and

reduce moisture. 3 / 4

8.Which factor most affects the capacity of an air compressor?

• Pipe color
• Lubricant smell
• Intake air pressure and temperature
• Tank paint

Rationale: Cooler, denser intake air increases compressor capacity.

9.

A pressure switch is used to:

• Measure humidity
• Control oil level
• Start and stop the compressor at preset pressures
• Control room temperature

Rationale: Pressure switches regulate compressor cycling based on system

pressure.

10.

Moisture in compressed air systems is removed using:

• Exhaust fans
• Chlorine filters
• Aftercoolers and moisture separators
• Lighting systems
• / 4