FDNY A35 EXAM Key Questions and Correct
Air compressors power... - CORRECT ANSWERS (1) industrial equipment and (2) construction
tools
Examples of equipment powered by air compressor - CORRECT ANSWERS pneumatic wrenches,
lifts in auto service stations, paint spray booths
Air compressors enable... - CORRECT ANSWERS (1) efficient repair of all types of vehicles; and
(2) facilitate their safe operation on public thoroughfares
Permit is required for air compressor - CORRECT ANSWERS that compresses air above 100 PSI
Types of air compressors - CORRECT ANSWERS (1) reciprocating;
(2) centrifugal;
(3) solar; and
(4) rotary
*Difference is the way in which they compress air
How do air compressors work - CORRECT ANSWERS take the air in a room and force it into a
container UNDER PRESSURE. The more air forced into the container, the greater the pressure.
Compressed air can be discharged from the container at a controlled rate.
Most common air compressor - CORRECT ANSWERS Reciprocating
Air compressors are sometimes called - CORRECT ANSWERS air pumps
Air compressors can be powered by: - CORRECT ANSWERS (1) electric motors;
(2) internal combustion engines; or
, (3) steam turbines
Explosions & air compressors - CORRECT ANSWERS If there is a build up of flammable gases
(ex: in service stations and workshops), those gases are heavier than air and fall to the floor before
spreading outward. These gases are easily ignited by sparks and high temperatures--which INCLUDES
the heat generated by an air compressor.
To avoid explosions w/ air compressors - CORRECT ANSWERS Raise air compressor at LEAST 5
feet above ground level so that no flammable gases are drawn into the compressor. To meet the height
requirement you can place compressor on a shelf or bench OR the air receiver tank may be turned and
stood on end w/ the air compressor bolted to the top of the tank.
Power to air compressor - CORRECT ANSWERS entire unit is driven by an electric motor. Motor
activates a series of drive belts. Belts power the moving parts of the unit--like w/ power steering and
alternator in automobile
Compression Chamber operation - CORRECT ANSWERS Air is compressed in compression
chamber which consists of a PISTON inside a CYLINDER. Piston moves up and down.
When piston moves down -->draws air into cylinder, through INTAKE VALVE (valve automatically
opens when piston moves down).
When piston moves up-->air is compressed (intake vale automatically closes to avoid air escaping from
cylinder).
Air Reciever Operation - CORRECT ANSWERS When air pressure reaches a certain level, it
forces open a DISCHARGE VALVE (which is spring loaded). This releases compressed air into air
reciever (aka air tank), which is what supplies compressed air when needed.
Single Stage Air Compressor - CORRECT ANSWERS with one cylinder and one piston
Multi Stage Air Compressor - CORRECT ANSWERS with more than one piston and cylinder.
Air compressors power... - CORRECT ANSWERS (1) industrial equipment and (2) construction
tools
Examples of equipment powered by air compressor - CORRECT ANSWERS pneumatic wrenches,
lifts in auto service stations, paint spray booths
Air compressors enable... - CORRECT ANSWERS (1) efficient repair of all types of vehicles; and
(2) facilitate their safe operation on public thoroughfares
Permit is required for air compressor - CORRECT ANSWERS that compresses air above 100 PSI
Types of air compressors - CORRECT ANSWERS (1) reciprocating;
(2) centrifugal;
(3) solar; and
(4) rotary
*Difference is the way in which they compress air
How do air compressors work - CORRECT ANSWERS take the air in a room and force it into a
container UNDER PRESSURE. The more air forced into the container, the greater the pressure.
Compressed air can be discharged from the container at a controlled rate.
Most common air compressor - CORRECT ANSWERS Reciprocating
Air compressors are sometimes called - CORRECT ANSWERS air pumps
Air compressors can be powered by: - CORRECT ANSWERS (1) electric motors;
(2) internal combustion engines; or
, (3) steam turbines
Explosions & air compressors - CORRECT ANSWERS If there is a build up of flammable gases
(ex: in service stations and workshops), those gases are heavier than air and fall to the floor before
spreading outward. These gases are easily ignited by sparks and high temperatures--which INCLUDES
the heat generated by an air compressor.
To avoid explosions w/ air compressors - CORRECT ANSWERS Raise air compressor at LEAST 5
feet above ground level so that no flammable gases are drawn into the compressor. To meet the height
requirement you can place compressor on a shelf or bench OR the air receiver tank may be turned and
stood on end w/ the air compressor bolted to the top of the tank.
Power to air compressor - CORRECT ANSWERS entire unit is driven by an electric motor. Motor
activates a series of drive belts. Belts power the moving parts of the unit--like w/ power steering and
alternator in automobile
Compression Chamber operation - CORRECT ANSWERS Air is compressed in compression
chamber which consists of a PISTON inside a CYLINDER. Piston moves up and down.
When piston moves down -->draws air into cylinder, through INTAKE VALVE (valve automatically
opens when piston moves down).
When piston moves up-->air is compressed (intake vale automatically closes to avoid air escaping from
cylinder).
Air Reciever Operation - CORRECT ANSWERS When air pressure reaches a certain level, it
forces open a DISCHARGE VALVE (which is spring loaded). This releases compressed air into air
reciever (aka air tank), which is what supplies compressed air when needed.
Single Stage Air Compressor - CORRECT ANSWERS with one cylinder and one piston
Multi Stage Air Compressor - CORRECT ANSWERS with more than one piston and cylinder.
