HVAC Ventilation Design 2

Question 1

According to ASHRAE 62.1, what is the minimum outdoor air ventilation rate for an office space occupied at 5 people per 1,000 sq ft?

Accepted Answer

10 cfm per person

Answer

ASHRAE 62.1 specifies 10 cfm per person as the minimum outdoor air rate for office occupancies under standard conditions.

Question 2

What does the term 'ventilation effectiveness' describe in HVAC design?

Accepted Answer

How efficiently outdoor air reaches the breathing zone

Answer

Ventilation effectiveness (Ev) measures how well the outdoor air delivered to a space actually reaches the occupants' breathing zone.

Question 3

A demand-controlled ventilation (DCV) system uses which sensor to modulate outdoor air intake?

Accepted Answer

CO2 sensor

Answer

DCV systems use CO2 sensors as a proxy for occupancy level to dynamically adjust outdoor air supply and reduce energy waste.

Question 4

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

Accepted Answer

ERV recovers both heat and moisture; HRV recovers heat only

Answer

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

Question 5

Which ventilation strategy introduces 100% outdoor air and exhausts 100% of return air, with no recirculation?

Accepted Answer

Once-through system

Answer

A once-through (100% OA) system uses no return air recirculation, making it ideal for spaces like laboratories and hospitals with contamination concerns.

HVAC Practice Test

HVAC Practice Test

HVAC Ventilation Design 2