Glossary
Terms explained in plain English
The words that come up when sizing a dehumidifier or comparing air purifiers — defined briefly, with links to the full guides.
Air Changes per Hour (ACH)
How many times the full volume of air in a room is replaced or processed in an hour — a measure used for ventilation and air purifier sizing.
CADR (Clean Air Delivery Rate)
A measured rate of clean, particle-free air an air purifier actually delivers — the number that tells you if it's sized for your room.
Desiccant vs Refrigerant Dehumidification
Two ways to remove moisture from air: a cold coil that condenses it (refrigerant) or a moisture-absorbing material regenerated with heat (desiccant).
Dew Point
The temperature at which air becomes saturated with moisture and condensation starts to form.
Extraction Rate (L/day)
How many litres of water a dehumidifier removes from the air in 24 hours under stated test conditions — the headline capacity number.
HEPA (High-Efficiency Particulate Air filter)
A dense filter mesh that physically traps fine airborne particles, including PM2.5-sized smog and dust.
Psychrometrics
The branch of physics dealing with the properties of moist air — temperature, humidity, dew point and volume, and how they relate to each other.
Relative Humidity (RH)
The amount of moisture in the air as a percentage of the maximum it could hold at that temperature.