NAFA CAFS Test 2025 with precise || || || || || ||
detailed solutions ||
Aerosols cover a wide range of sizes. True or false? - Correct answer ✔True.
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NAFA Guide to Air Filtration, 5th ed. 2014, page 1.2
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A micron is approximately ___________ of an inch. - Correct answer
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✔1/25,400". ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 1.2
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Particle counters used to use tungsten light, and were limited to measuring
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particle sizes down to 0.3 microns. Newer units, using ___________ as a source
|| || || || || || || || || || || || ||
of light, have the capability of counting particles smaller than 0.1 micron. -
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Correct answer ✔Lasers.
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NAFA Guide to Air Filtration, 5th ed. 2014, page 1.5
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If you have a 20x24x12 filter, with 48sq. ft. of media, placed in an airstream of
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2000cfm, what would your velocity(fpm) be? - Correct answer ✔41.66fpm.
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V(fpm)=Q(cfm)/A(Sq. ft. of media) || || ||
, NAFA Guide to Air Filtration, 5th ed. 2014, page 2.1
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Electronic Air Cleaners are externally powered devices. True or false? - Correct
|| || || || || || || || || || || ||
answer ✔True. || ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 2.3
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The thicker the filter media and the closer the orientation of fibers, the
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________ the possibility of collision by a fiber. - Correct answer ✔Greater.
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NAFA Guide to Air Filtration, 5th ed. 2014, page 2.4
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Impingement filters are frequently treated with adhesives that coat the fibers
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and create a bond between the particle and the fiber. True or false? - Correct
|| || || || || || || || || || || || || || ||
answer ✔True. ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 2.5
|| || || || || || || || ||
A dipole moment is when there is a ________ _____________ of electrons at
|| || || || || || || || || || || || ||
____ _______ or _____ of a molecule than there is at ____________. - Correct
|| || || || || || || || || || || || || ||
answer ✔Greater concentration.
|| ||
One point or end.
|| || ||
Another.
detailed solutions ||
Aerosols cover a wide range of sizes. True or false? - Correct answer ✔True.
|| || || || || || || || || || || || || ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 1.2
|| || || || || || || || ||
A micron is approximately ___________ of an inch. - Correct answer
|| || || || || || || || || || ||
✔1/25,400". ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 1.2
|| || || || || || || || ||
Particle counters used to use tungsten light, and were limited to measuring
|| || || || || || || || || || || ||
particle sizes down to 0.3 microns. Newer units, using ___________ as a source
|| || || || || || || || || || || || ||
of light, have the capability of counting particles smaller than 0.1 micron. -
|| || || || || || || || || || || || ||
Correct answer ✔Lasers.
|| ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 1.5
|| || || || || || || || ||
If you have a 20x24x12 filter, with 48sq. ft. of media, placed in an airstream of
|| || || || || || || || || || || || || || || ||
2000cfm, what would your velocity(fpm) be? - Correct answer ✔41.66fpm.
|| || || || || || || || ||
V(fpm)=Q(cfm)/A(Sq. ft. of media) || || ||
, NAFA Guide to Air Filtration, 5th ed. 2014, page 2.1
|| || || || || || || || ||
Electronic Air Cleaners are externally powered devices. True or false? - Correct
|| || || || || || || || || || || ||
answer ✔True. || ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 2.3
|| || || || || || || || ||
The thicker the filter media and the closer the orientation of fibers, the
|| || || || || || || || || || || || ||
________ the possibility of collision by a fiber. - Correct answer ✔Greater.
|| || || || || || || || || || ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 2.4
|| || || || || || || || ||
Impingement filters are frequently treated with adhesives that coat the fibers
|| || || || || || || || || || ||
and create a bond between the particle and the fiber. True or false? - Correct
|| || || || || || || || || || || || || || ||
answer ✔True. ||
NAFA Guide to Air Filtration, 5th ed. 2014, page 2.5
|| || || || || || || || ||
A dipole moment is when there is a ________ _____________ of electrons at
|| || || || || || || || || || || || ||
____ _______ or _____ of a molecule than there is at ____________. - Correct
|| || || || || || || || || || || || || ||
answer ✔Greater concentration.
|| ||
One point or end.
|| || ||
Another.
