IAQ stands for Indoor Air Quality, the condition of the air inside a building and its potential effects on health and comfort. There is no single universal IAQ number that captures every contaminant. Monitors measure specific parameters or calculate a device-specific score
Common Measurements
CO₂: helps assess outdoor-air ventilation relative to occupancy.
PM2.5 / PM10: measure fine or inhaling airborne particles.
VOCs / TVOC: indicate some chemical vapors from materials and household activities.
Relative humidity: helps evaluate moisture, comfort and condensation risk.
Outdoor AQI color bands should not be presented as a universal indoor-air-quality scale. Indoor sensors, pollutants and measurement units need their own explanations. A good IAQ strategy combines source control, ventilation, filtration, humidity management and maintenance.