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FDNY A-35 questions with answers graded A+
Question 1: Air compressors power...
CORRECT ANSWER : (1) industrial equipment and (2)
construction tools
Question 2: Examples of equipment powered by air compressor
CORRECT ANSWER: pneumatic wrenches, lifts in auto service
stations, paint spray booths
Question 3: Air compressors enable...
CORRECT ANSWER : (1) efficient repair of all types of
vehicles; and (2) facilitate their safe operation on public thoroughfares
Question 4: Permit is required for air compressor
CORRECT ANSWER : that compresses air above 100 PSI
Question 5: Types of air compressors
CORRECT ANSWER : (1) reciprocating; (2) centrifugal; (3)
solar; and (4) rotary
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Question 6: How do air compressors work
CORRECT ANSWER : 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.
Question 7: Most common air compressor
CORRECT ANSWER : Reciprocating
Question 8: Air compressors are sometimes called
CORRECT ANSWER : air pumps
Question 9: Air compressors can be powered by:
CORRECT ANSWER : (1) electric motors; (2) internal
combustion engines; or (3) steam turbines
Question 10: Explosions & air compressors
CORRECT ANSWER : 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
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gases are easily ignited by sparks and high temperatures--which INCLUDES the heat generated by an air compressor.
Question 11: To avoid explosions w/ air compressors
CORRECT ANSWER : 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.
Question 12: Power to air compressor
CORRECT ANSWER : 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
Question 13: Compression Chamber operation
CORRECT ANSWER : 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
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automatically opens when piston moves down). When piston moves up-->air is compressed (intake vale automatically closes to avoid air escaping from cylinder).
Question 14: Air Reciever Operation
CORRECT ANSWER : 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.
Question 15: Single Stage Air Compressor
CORRECT ANSWER : with one cylinder and one piston
Question 16: Multi Stage Air Compressor
CORRECT ANSWER : with more than one piston and cylinder.
Each cylinder will increase the pressure of the air by taking air from the discharge side of the previous cylinder and increasing the pressure to a new level. Once it reaches the last level, the pressurized air is discharged into the reciever.
