Ozone generators are being promoted as an effective method to clean indoor air pollution and odours. However ozone is a lung irritant that can cause adverse health effects.
Ozone generators are being promoted as an effective method to clean indoor air pollution and odours. However ozone is associated with adverse health effects.
Available scientific evidence shows that ozone concentrations that are safe to breathe are unlikely to be effective in controlling indoor air pollution.
Manufacturers and vendors of ozone devices use a variety terms to describe ozone. Terms such as "energized oxygen" or "pure air" suggest that ozone is a "healthy" kind of oxygen. However, ozone is a toxic gas with very different properties to oxygen. Whether it is a pure form or mixed with other chemicals, ozone can be harmful to health.
Ozone, O3, is composed of three atoms of oxygen. Two atoms of oxygen form the basic oxygen molecule. The additional third atom makes ozone an unstable, highly reactive gas. The ozone layer in the upper atmosphere helps filter out damaging ultraviolet radiation from the sun, but ozone in the air we breathe is irritative to the eye, nose, throat and lungs and can have a significant negative impact on health.
These proven adverse health effects have resulted in the Australian Government setting standards for ozone in outdoor air.
An ozone generator is a device designed to produce the gas ozone. Ozone is used effectively in water purification, but ozone in air must reach high levels to remove air pollutants.
Health experts warn that it is important to control conditions to ensure that no person or pet becomes exposed to high levels of ozone. Ozone also masks the odour of some pollutants by impairing a person's sense of smell.
Further, ozone is not effective for killing bacteria or mould in materials such as air conditioning duct lining and ceiling tiles.
Some people are more susceptible than others and may be more likely to experience adverse health effects. People at particular risk are children, the elderly and people with asthma.
There are several simple and effective methods of controlling indoor air pollution and odours, including source control, ventilation and air cleaning. It is important to note that mould is a common source of odours in homes.
Source control is most effective and easy to implement:
Ventilation is also effective and commonly used:
Air cleaning by itself does not adequately reduce indoor air pollution, however it can be used in combination with source control and ventilation. Air filters, electronic particle air cleaners and ionizers can be used to remove airborne particles. Gas adsorbing material (eg activated charcoal) is sometimes used to remove gaseous pollutants. Air cleaners are relatively costly.
To be effective they require proper sizing, installation and use (according to the manufacturers directions), and maintenance, so they are more suitable for use in workplaces rather than homes. Maintenance costs, such as replacement of filters, can be significant. If you choose to use an air cleaner such as an electrostatic precipitator or ionizer in your home or work, it is important to ensure that it does not produce ozone as a by-product.