Indoor Air Quality and Filtration Flashcards
7 cards from real HVAC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Indoor Air Quality and Filtration flashcards as text
When performing an IAQ investigation, which instrument measures airborne particulate matter concentration?
Answer: Particle counter
A particle counter measures the number and size distribution of airborne particles per cubic foot or cubic meter of sampled air.
What is the term for the condition where chemical contaminants from one area migrate into another area through HVAC ductwork or building pressurization?
Answer: Cross-contamination
Cross-contamination occurs when airborne pollutants from one zone — such as a copy room or lab — migrate through shared HVAC systems into occupied spaces.
Which ASHRAE standard covers residential ventilation requirements, including whole-house mechanical ventilation?
Answer: ASHRAE 62.2
ASHRAE 62.2 specifically addresses ventilation and IAQ requirements for low-rise residential buildings, including whole-building and local exhaust strategies.
A technician finds microbial growth on cooling coil surfaces. Besides cleaning the coil, what HVAC design factor should be corrected to prevent recurrence?
Answer: Ensure the drain pan slopes properly and condensate drains freely
Standing water in improperly draining condensate pans provides the moisture environment that sustains biological growth on cooling coils.
What does the term 'dilution ventilation' mean in IAQ practice?
Answer: Introducing outdoor air to reduce indoor contaminant concentrations
Dilution ventilation reduces indoor pollutant concentrations by mixing clean outdoor air with contaminated indoor air until acceptable levels are achieved.
Which action is most effective at reducing volatile organic compounds (VOCs) introduced by new building materials during initial occupancy?
Answer: Conducting a flush-out with 100% outdoor air at maximum ventilation rates before occupancy
A pre-occupancy flush-out using maximum outdoor air flow rates purges VOCs off-gassed by new materials before building occupants are exposed.
What is the primary limitation of portable air purifiers with HEPA filtration in large commercial spaces?
Answer: Their airflow capacity (CFM) is too low to adequately clean the air volume of large spaces
Portable HEPA units have limited CFM ratings designed for room-scale spaces, and multiple units or whole-building HVAC integration is required for larger commercial environments.