Many people regard their homes as having a pleasant and clean atmosphere. Marketers over the years have tried to sell us a huge range of things we may, or more likely, may not, need to improve our lives. One such item many people have gone out of their way to buy is an air purifier. Whilst the range and effectiveness of air purifiers can often be great at cleaning the air we breathe in our houses, some manufacturers have been literally misleading and dangerous.

If anyone has bought an ozone air purifier they should seriously reconsider its use.

You've probably heard of ozone before. It naturally occurs in our earth's outermost atmosphere called the stratosphere, around 20km above our heads. Ozone protects us from the many lethal UV rays coming from space.

Ozone its self is a hugely reactive form of oxygen compound occurring as a gas with a very short half-life. The compound has three, as opposed to two oxygen atoms, and decays to form the more familiar two oxygen atom compound. Ozone is created by UV (largely from our sun) breaking oxygen molecules into single highly reactive oxygen atoms that combine with other oxygen molecules to from a triple oxygen atom molecule, ozone. To a far lesser extent ozone is also created at waterfalls and through the high voltages associated with lightning.

Ozone doesn't represent a problem when inhaled from natures small quantities produced at ground level. But when levels inside your own house reach above recognized safety limits this gas is potentially life threatening.

Air purifiers are not a new phenomenon, people have bought from the wide variety on offer for well over a decade. A more recent introduction to the range has been an air purifier that operates with ozone, charging airborne polluting particles and attracting them to electrodes. Ozone is a by-product of this ionization process. Past experiments have been made using a variety of ozone producing air purifiers that sought to establish ozone levels emitted whilst in use in a range of environments. Findings were that a number of models produced ozone levels in excess of 350 parts per billion, sufficient to enable a stage 2 smog alert in an outdoor environment!

Rooms that had the most pronounced increases in ozone were those containing the least ventilation and a predominance of slow reacting materials like ceramic and plastic tiles. Carpets, rubbers and cloths were found to neutralize the ozone threat by quickly reacting with the ozone, destroying it in due course.

Ozone in above recognized safe levels reacts fast with living tissues leading to the developing of asthmatic conditions, coughing, throat irritation, shortness of breathing, chest pains, extensive lung epithelial damage and strong headaches.

Some manufacturers creating these dangerous domestic appliances have offered yet further danger through poor operating advice. Instructions have been reported to say that the air purifier should be turned up in power until the 'fresh laundry scent' is smelt. Since human perception of a constant scent is diminished over time this tends to result in people turning the machine up in power consistently to keep that smell detectable.

With this information in mind, if you believe you have poor quality air in your household you would do best to look at the other far more effective and safe air purifiers currently on the market. If possible try to get an air quality test done, this helps you to know what type of air purifier you may require, since many models act on specific air pollutants, e.g. mould and pathogens, or dust and gasses.

Ozone is produced in harmless quantities by many electric appliances, e.g. computers and TV's, central heating, fireplaces, fridges and even our cars. Typically these quantities are no larger than the natural levels found outside. The only place large quantities of ozone should really ever be found is in the outer atmosphere.