Air purifiers that use ionizers and electrostatic precipitators produce ozone as a byproduct of their operation. These types of air purifiers don't intentionally create ozone; instead, it's an unintended consequence of the technology they employ to clean the air.
Ozone Production in Ionizing Air Purifiers
Ionizing air purifiers work by emitting negative ions. These ions attach to airborne particles, giving them a negative charge. The charged particles are then attracted to surfaces with an opposite charge (positive), such as walls or furniture, or to a collection plate within the purifier.
However, the process of generating these negative ions can also lead to the formation of ozone (O3). This happens when oxygen molecules (O2) in the air are split by the high voltage electricity used in the ionizer. These single oxygen atoms (O) can then combine with other oxygen molecules (O2) to form ozone (O3).
Ozone Production in Electrostatic Precipitators
Electrostatic precipitators use a similar process to ionizers, first charging airborne particles and then collecting them on plates. Like ionizers, electrostatic precipitators can also generate ozone as a byproduct of the high-voltage electrical fields they use to charge the particles. The electrical discharge involved in charging the particles can break down oxygen molecules, leading to the creation of ozone.
Why Ozone is a Concern
While ozone can be used as a disinfectant in high concentrations, it's considered an air pollutant at levels that can be produced by some air purifiers. Exposure to ozone can cause:
- Coughing and throat irritation
- Worsening of asthma symptoms
- Shortness of breath
- Chest pain
Therefore, it's important to choose air purifiers that don't intentionally produce ozone or that have been tested to ensure they meet acceptable ozone emission limits. Many modern air purifiers use HEPA filters and activated carbon filters, which do not generate ozone.
