Indoor Air Quality Glossary

Plain-English explainers for the technical terms, rebates, regulations, and acronyms that show up when you shop for Indoor Air Quality systems and services. Each entry links the underlying source, lists the numbers that matter, and points to related concepts.

ACAC Certification (CIE / CIEC)
The only CESB-accredited indoor-air-quality credential — the clearest sign an IAQ assessor knows the science.
ASHRAE 62.2 (Residential Ventilation Standard)
The national standard for how much fresh air a home needs — the spec a whole-house ventilation install is sized to.
Bipolar Ionization (NPBI)
A heavily marketed 'active' air-cleaning add-on with weak independent evidence — treat it as a red flag, not a feature.
CADR (Clean Air Delivery Rate)
The AHAM-standardized number for how much clean air a purifier actually delivers — and how to size one to a room.
ERV vs HRV (Energy / Heat Recovery Ventilator)
Two ways to bring in fresh air without wasting energy — in humid Texas or Florida, the moisture difference decides.
HEPA (High-Efficiency Particulate Air Filter)
The gold-standard particle filter — 99.97% at 0.3 microns — and why whole-home HEPA needs a bypass, not a filter slot.
MERV 13 (Minimum Efficiency Reporting Value)
The filtration grade EPA points homeowners to — catches fine particles, low enough for a normal HVAC system to run.
PM2.5 (Fine Particulate Matter)
The microscopic particles that drive most air-quality health concern — and the pollutant whole-home filtration targets.
Relative Humidity Setpoint (30–60% Rule)
Keep indoor humidity in the right band to starve mold and dust mites and kill that muggy or bone-dry feeling.
Source Control (EPA's #1 IAQ Strategy)
The EPA's most effective — and cheapest — way to clean indoor air: remove or reduce the pollutant at its source first.
UL 2998 (Zero Ozone Emissions Validation)
The badge that proves an air cleaner doesn't make ozone — demand it before any 'active' purifier goes in your ducts.
UVGI / UV-C (Germicidal UV Light)
In-duct germicidal lamps that disinfect air and keep the AC coil clean — a layer, not a substitute for filtration.
VOCs (Volatile Organic Compounds)
The off-gassing chemicals from paint, furnishings, and cleaners — far higher indoors, best handled at the source.
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