Pollution levels in buildings are often left unmonitored. A whole mixture of substances can enter the air, depending upon the situation, steadily harming people in the vicinity.

A whole range of air purifiers have been developed to try to deal with this common problem, e.g. mechanical or chemical filtering, and ionizing particles. Ozone use is one method that has received many critics.

Manufacturers often claim that their ozone air purifiers get rid of almost every harmful contaminant in the air. This statement is unfortunately incorrect!

Ozone has been shown to take a potentially long time to react with air pollutants, from a few months to a few years! Additionally, ozone is not capable of reacting with every chemical it comes into contact with. Manufacturers sometimes reckon that their product can be highly successful at removing carbon dioxide and formaldehyde. This claim has also reportedly been found to be untrue, via scientific analysis.

Ozone is readily capable of reacting with a number of commonly found air-borne pollutants creating compounds that are likewise irritating or harmful.

Ozone is not able to remove most of the particles that lead to allergies, e.g. dust and pollen. Electrostatic precipitators and high efficiency particle filters have been seen to be more effective than some ozone purifiers with ionizers built in at removing harmful particles from the air.

When used at levels that have been deemed by the authorities to be safe, ozone has been found ineffective at ridding biological air-bound pollutants such as bacteria, viruses and mould.

Much controversy has erupted over this type of air purifier system. Ozone is well acknowledged as a very dangerous chemical compound, hugely irritating in tiny quantities, potentially lethal at mid to higher levels.

When choosing to purchase a particular type of air cleaning device you should ideally review a guide detailing the latest findings and comparisons. The guide in question should be thorough, covering a wide number of aspects that are not always mentioned. Four worth considering are:

• ozone emissions
• total emitted whilst in operation
• efficiency of chemical removal
• percentage of formaldehyde and volatile organic compounds (VOC) removed from the air
• efficiency of odor removal
• measured reduction in odor perception
• efficiency of particle removal
• quantity of dust taken out of the air, expressed as a percentage

Remember that you should try to use an air cleaner that removes the particular pollutants that appear in you air-space. Try and run tests to see which pollutants are present, and then how various air purifiers control them, if possible. Some independent companies or government monitoring bodies will assist you with this.