Ventilation & Indoor Air Quality Flashcards
7 cards from real HERS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Ventilation & Indoor Air Quality flashcards as text
Which ASHRAE standard governs minimum mechanical ventilation requirements for residential buildings rated under the HERS program?
Answer: ASHRAE 62.2
ASHRAE 62.2 is specifically the ventilation standard for low-rise residential buildings, which applies to homes evaluated under the HERS rating system.
Using the ASHRAE 62.2 formula, what is the minimum required whole-building mechanical ventilation rate for a 1,500 sq ft home with 3 bedrooms?
Answer: 45 CFM
The ASHRAE 62.2 formula is 0.01 × floor area + 7.5 × (bedrooms + 1) = 0.01×1,500 + 7.5×4 = 15 + 30 = 45 CFM.
In a tight home with a blower door result at or below 3 ACH50, ASHRAE 62.2 requires mechanical ventilation primarily to:
Answer: Dilute indoor pollutants and maintain acceptable indoor air quality
Mechanical ventilation in tight homes ensures sufficient fresh air exchange to dilute pollutants like CO2, VOCs, and moisture that accumulate when natural infiltration is insufficient.
Per ASHRAE 62.2, the measured airflow of a mechanical ventilation system must be within what tolerance of the design rate to be considered compliant?
Answer: ±10%
ASHRAE 62.2 requires that measured ventilation airflow be within ±10% of the design airflow rate to confirm the system is performing as intended.
Which of the following ventilation system types provides the greatest control over both supply and exhaust airflow rates in a residence?
Answer: Balanced ventilation
Balanced ventilation systems control both supply and exhaust airstreams independently, providing the most precise management of ventilation rates and building pressurization.
Under ASHRAE 62.2, which type of local ventilation is required in addition to whole-building mechanical ventilation?
Answer: Spot ventilation for kitchens and bathrooms
ASHRAE 62.2 Section 5 requires separate local exhaust ventilation (spot ventilation) for kitchens and bathrooms to remove source pollutants, independent of whole-building requirements.
Per ASHRAE 62.2, kitchen exhaust fans with airflow ratings at or below 400 CFM must have a maximum sound rating of:
Answer: 3 sones
ASHRAE 62.2 Section 5.1 limits kitchen exhaust fan noise to a maximum of 3 sones for intermittent fans rated at or below 400 CFM to encourage occupant use.