NCT Air Filtration Fundamentals & Filter Media 2

Question 1

ASHRAE Standard 52.2 is used to evaluate air filter performance primarily by measuring:

Accepted Answer

Particle size efficiency and dust holding capacity

Answer

Energy consumption and airflow volume

Answer

Filter media tensile strength

Answer

Carbon adsorption capacity

Question 2

What is the primary purpose of activated carbon in an air filter?

Accepted Answer

Adsorbing gaseous pollutants and odors

Answer

Capturing sub-micron particles

Answer

Increasing filter media strength

Answer

Reducing static pressure drop

Question 3

As a filter loads with dust during service, what generally happens to both its efficiency and pressure drop?

Accepted Answer

Efficiency increases; pressure drop increases

Answer

Efficiency increases; pressure drop decreases

Answer

Efficiency decreases; pressure drop decreases

Answer

Efficiency decreases; pressure drop stays constant

Question 4

Which filter construction type offers the greatest filter media surface area within a compact housing frame?

Accepted Answer

V-bank (V-pleat) filter

Answer

Flat panel filter

Answer

Bag filter

Answer

Cartridge filter with deep pleats

Question 5

Fiberglass filter media is commonly used in low-MERV panel filters because it offers:

Accepted Answer

Low cost, low resistance, and acceptable efficiency for coarse dust

Answer

High chemical resistance and moisture absorption

Answer

Superior submicron particle capture

Answer

Long service life with no pressure drop increase

Question 6

The Dust Holding Capacity (DHC) of a filter is important because it directly affects the filter's:

Accepted Answer

Service life and replacement interval

Answer

Initial particle capture efficiency

Answer

MERV rating category

Answer

Frame material selection

Question 7

In the context of NAFA certification, what does the term 'fractional efficiency' describe?

Accepted Answer

The efficiency of a filter at specific particle size intervals

Answer

The percentage of total airflow that bypasses the filter

Answer

The ratio of filter face area to total duct area

Answer

The fraction of filter media that is active vs. inert