Ventilation, air purification and air conditioning are often confused, but the three have very different effects on indoor air.
Ventilation is the process by which fresh new air (usually from outdoors) is intentionally provided to habitable rooms (bedrooms, living rooms, etc) and polluted air is removed via wet rooms (kitchen, bathroom, toilet etc) [3]
Unbalanced ventilation systems with only an extract and no supply system cannot satisfy all the given requirements of a ventilation system [4].
Without ventilation introducing new fresh air for occupants to breathe, metabolic Carbon Dioxide (CO2) builds-up, displacing oxygen from airtight occupied spaces. At high concentrations, CO2 does not only cause asphyxiation but also acts as a toxicant [5].
Air purification is the process of removing particulates and gases from indoor air.
Air purification cleans and recirculates the same air but does not introduce new fresh air into a home.
It is also unable to remove all gases and finer particulates that are too small for most filters to capture.
Air conditioning is the process of removing heat from a space to achieve a more comfortable interior temperature.
Air conditioning cools and recirculates the same air but does not introduce new fresh air into a home a home.
References:
[3] Liddament, M. (2000) A review of ventilation and the quality of ventilation air. National Library of Medicine. Indoor Air. 2000 Sep;10(3):193-9
[4] EN 13141-7:2021 (2024) Ventilation for buildings – Performance testing of components/products for residential ventilation. CEN European Committee for Standardisation.
[5] Ikeda, N., Takahashi, H., Umetsu, K., and Suzuki, T. (1989) The course of respiration and circulation in death by carbon dioxide poisoning. Forensic Sci Int – National Library of Medicine. 1989 Apr-May;41.
