Trusted Guide for Exam Mastery!
When is an FDNY permit required for a compressor? - If it is used to compress any non-flammable,
corrosive or oxidizing gas including air to a pressure exceeding 100 psi. Includes a fair or festival.
When is a permit not required? Who issues this permit? - Outdoor air compressing. Bureau of fire
prevention.
Different types of air compressors - Reciprocating, centrifugal, rotary, and scroll. Most common is
reciprocating. Difference is the way in which they compress the air.
How can air compressors be powered? - Electric motor (most common), internal combustion
engines, or steam turbines.
Flammable gases - Heavier than air and falls to the floor and spreads outward. Easily ignited by
sparks and high temps. If inside compressor can cause explosion.
How far must air compressor be from ground to avoid flammable gases? Where? - 5 feet on a shelf
or bench or on top of the air receiver tank.
How does the air compressor operate? - Motor activates drive belts then belts serve power to
moving parts of unit.
What happens in the compression chamber? - There is a piston in a cylinder. The piston moves up
and down and when it moves down it draws in air through intake valve. Intake valve closes when it is
up and prevents air from escaping the cylinder which compresses the air.
What does the discharge valve do? - Opens when pressure reaches a certain level and is spring
loaded. When it opens the compressed air is released into air receiver sometimes called air tank.