Your browser does not support JavaScript!
Like everyone else, we use cookies. You can learn more about their use by reading our privacy policy.

Which is the best air purifier? - How to choose your air purifier?

Indoor air purifiers have multiplied in recent years. All promise to help us breathe at home a healthier air. The offer is so wide that navigating the vast array of available air purifiers can be confusing. Technologies range from filtration to air ionization, plasma, ozonation, and photocatalysis. How to choose the right device? TEQOYA provides you some answers.

What does an air purifier do?

Aeration of the room

Do you suffer from your indoor air pollution, or do you simply want to take care of yourself and your loved ones? The air purifier is a device for you. By fighting indoor pollution, it relieves people with respiratory problems, asthma and allergies. The air purifier also allows you to improve your day-to-day well-being.

The classic air purifier with filters

The classic air purifier is based on an air filtration system. It usually consists of several superimposed filters: a pre-filter, a HEPA filter, and an activated carbon filter.

1. The pre-filter

The air purifier pre-filter stops visible particles larger than a micron. It thus limits the clogging speed of the other filters, and increases their lifespan. Indeed, the higher the filtration power, the more the filter gets dirty quickly.

2. The activated carbon filter

The activated carbon filter is used to capture chemical pollutants, that is, odors and gases in the indoor air. It acts by adsorption: the molecules of gas, put in contact with the active carbon, are incorporated in the totality of its volume. Activated carbon filtration is a complex technology that is difficult to control. It depends on many factors, resulting in an often uncertain efficacy. Adsorption is also a matter of balance between the adsorbent and the surrounding air, which means that the adsorbent material can release the gases it has trapped if the surrounding air conditions change.

Discover our article on activated carbon filters

3. The HEPA filter

HEPA is an acronym for High Efficiency Particulate Air English. Under laboratory conditions, the HEPA filter air purifier captures at least 99.97% of the 0.3 micrometer diameter particles.

This percentage is to be put into perspective in several respects:

  • 90% of the suspended particles, including bacteria spores and viruses, are smaller in size.
  • According to a recent study, the HEPA filter loses 25% efficiency in the space of 6 months, in a slightly polluted environment.
  • In practice, according to the same study, the HEPA filter air purifier achieves a 68% reduction in ultrafine particle pollution.

Discover our article on HEPA filters

The air purifier with filters, what are the disadvantages?

1. The filter air purifier requires demanding and expensive maintenance

Maintenance of the air purifier with filters

The clogging of the filters implies a regular maintenance of the air purifier. Filter replacement can be tricky as pollutants disperse easily into the air during the operation. Yet it is essential: an untreated air purifier becomes a source of air pollution!

2. The filter air purifier is a source of noise and drafts.

Noise of the air purifier with filters

For maximum power, the air velocity in the unit must be high. The higher it is, the noisier the device. The number of filters is also decisive. The more filters, the less HEPA and activated carbon filters get dirty quickly; many filters, on the other hand, reduce airflow or increase noise, drafts and energy consumption.

3. The materials used in HEPA filters are potentially harmful

HEPA filters are commonly manufactured with Type 475 glass microfibers, which have been classified as carcinogens by public bodies and are materials whose human exposure is monitored and controlled in an industrial environment. Similarly, the recycling of these materials is framed. HEPA filters are therefore products to handle with care, and it is advisable not to throw them like any other waste, because microfibres can be dangerous if they are released into the air.

What alternatives to the air purifier with filters? Can those be relied upon?

The air purification market is booming. To overcome the defects of conventional filtration systems, new techniques are developing: photocatalysis, ozonation, plasma, and finally ionization. All these technologies are not equal! Some devices even degrade the quality of indoor air, emitting secondary pollutants more harmful than the primary pollutants targeted. The air purifier should therefore be chosen with care.


  • Principle

Photocatalysis is the mineralization of pollutants under the action of light rays on the surface of a catalyst, usually titanium dioxide (TiO2). In theory, the finalized process essentially produces water and carbon dioxide. The photocatalytic air purifier is highly effective on volatile organic compounds, inorganic pollutants and microorganisms.

  • Limits / disadvantages

In practice, the photocatalysis reaction is often incomplete, resulting in the emission of by-products into the air (e.g. ketones, aldehydes, organic acids). These secondary pollutants, toxic and / or irritating, are potentially more dangerous to health than the primary species treated.

Discover our article on photocatalysis


  • Principle

Used in a professional environment, ozonation consists of producing ozone (O3) in large quantities. Ozone is effective on chemical and biological contaminants. It is a powerful disinfectant.

  • Limits/disadvantages

Ozone is a very powerful oxidant, it is effective only from concentrations in the air dangerous for health. It contributes to irritation of membranes and mucous membranes, causing respiratory problems, coughing fits and asthma. It also reacts with indoor air pollutants to form potentially harmful secondary pollutants. French and European regulations set an average daily exposure target of less than 60 ppb, well below the concentration emitted by an ozonizer.

Cold plasma

  • Principle

The cold plasma technique is the mineralization of organic molecules through oxidation reactions initiated by free radicals produced by ionization. Under experimental conditions, the air purifier based on this principle is effective on volatile organic compounds, inorganic pollutants and microorganisms.

  • Limits/disadvantages

In practice, like photocatalysis, the mineralization is often incomplete, hence the emission of dangerous secondary pollutants. There are also emissions of ozone in the air, leading to the formation of harmful secondary pollutants, and oxides of nitrogen.

Air ionization

  • Principle

The ionizing air purifier is an important source of electrons (and thus negative ions) which, once released, combine and negatively charge the particles (initially neutral or positively charged). The particles are then precipitated to the soil by coalescence, repulsion of the particles of the same charge and attraction to the surfaces. The ionizer air purifier claims efficiency on biological and chemical contaminants, but also an improvement in well-being.

  • Limits/disadvantages

Most air ionizers emit a toxic gas: ozone. This gas, with a characteristic odor similar to that of bleach, is harmful. Before acquiring an air ionizer, it is important to ensure that it does not emit ozone!

TEQOYA, the ozone-free and eco-friendly air purifier

Everyone should be able to breathe healthy air. But the classic air purifiers, bulky and noisy, which we must regularly replace the filters, are too restrictive. And purify the air should not be at the expense of the planet but in the respect of people and the environment! Undeniably, the TEQOYA ionizer provides the answer more suited to daily use: efficiency against 99% of ultrafine particles, long life, comfort of optimal use, low power consumption, and respect for the environment.

Discover our range of air purifiers


Information on air quality and news from TEQOYA

How does an air ionizer work?

November 27th 2021

Natural environments are rich in negative ions. This is precisely the principle on which the air ionizer is based on. However, do you know how this technology manages to capture the pollution particles contained in the indoor air to purify your home?


Are air purifiers effective against viruses, especially the coronavirus COVID-19

October 20th 2020
#Virus and microorganismes   #L'essentiel  

In December 2019, a respiratory virus of the Coronavirus family appeared in the Wuhan region of China and has now spread to all continents.


What is eco-responsibility?

October 27th 2021

Purifying indoor air while protecting your health and the planet is possible! Say goodbye to filters and make way for negative ions: choose an eco-responsible air purifier that will easily reduce energy and resource consumption.


Read all our articles