HVAC Indoor Air Quality and Filtration 2

Question 1

What does a MERV rating measure in air filters?

Accepted Answer

Minimum Efficiency Reporting Value — particle capture efficiency

Answer

MERV (Minimum Efficiency Reporting Value) rates a filter's ability to capture airborne particles on a scale of 1–16.

Question 2

Which IAQ pollutant is a naturally occurring radioactive gas that can accumulate in basements?

Accepted Answer

Radon

Answer

Radon is a colorless, odorless radioactive gas that seeps from soil and rock and can reach dangerous concentrations in poorly ventilated lower levels.

Question 3

What is the primary purpose of an energy recovery ventilator (ERV) compared to a heat recovery ventilator (HRV)?

Accepted Answer

ERV transfers both heat and moisture; HRV transfers heat only

Answer

An ERV transfers both sensible heat and moisture (latent energy) between exhaust and supply airstreams, while an HRV transfers heat only.

Question 4

A MERV 13 filter is generally recommended for which application?

Accepted Answer

General residential use with standard HVAC equipment

Answer

MERV 13 filters capture particles as small as 0.3–1.0 microns and are widely recommended for improved residential and light commercial IAQ.

Question 5

What condition results when a building's HVAC system creates a negative pressure differential relative to the outdoors?

Accepted Answer

Backdrafting of combustion appliances

Answer

Negative building pressure can cause combustion gases from furnaces or water heaters to be drawn back into the living space instead of exhausted outside.

HVAC Practice Test

HVAC Practice Test

HVAC Indoor Air Quality and Filtration 2