How to choose an air cleaner in 2013?

The desire to improve our quality of life is forcing us to change our habits and pay more attention to the environment we come into contact with. We clean the water we drink. We carefully choose the products for our table, avoiding food with additives, dyes, flavorings, etc. d. We choose clothes made of natural fabrics. We try to make home renovations with environmentally friendly building materials. But we often forget something that surrounds us all the time – the air. But we come into contact with it every moment of our lives.

The air is clear – and therefore seems clean and safe to us. But this transparency is deceptive: the air can contain a huge variety of contaminants – dust particles and with them dust mites , pet hair and dander, plant pollen, viruses and bacteria, fungal spores, molecules of toxic chemicals.

All of them have adverse effects on human health, cause allergies, provoke infectious diseases, reduce body tonus. The proximity of industrial enterprises, thermal power plants, highways only worsens the situation. And has become a traditional plague in recent years – smoke and ash from forest fires – can also ruin our health and even cause poisoning.

Nevertheless, it is possible – and necessary – to improve the air quality in your home or office and make it cleaner! The more so that the market offers a wide range of devices that solve this problem – air purifiers.

Filtration methods

Air impurities are of different nature dust, volatile chemicals, microorganisms , so for its cleaning different types of filters are used, each of which performs its task. To ensure that the same air purifier can fight several problems at once, manufacturers usually equip their models with not one but several filters that complement each other in properties.

Filters are conditionally divided into several groups according to their functions – they detain mechanical particles, disinfect destroy microorganisms or inhibit their development and deodorize absorb odors and gases or deactivate their molecules . It is not rare that the filter combines several functions at once.

Let’s take a look at some common filters used in air purifiers.

HEPA filter.

It is one of the most popular elements used for mechanical air purification. The reason for that is its high efficiency, because it captures 99% of particles up to 0.3 microns, and among them are the majority of common allergens such as plant pollen, animal dander, fungal spores and a number of others .

For all its outstanding features the HEPA filter is rather simple in construction: in most cases it is made of a material similar to paper. The more surface area of the filter, the more contaminants it can trap, therefore HEPA filters are usually made corrugated.

HEPA filters are not regenerable and must be replaced as they become soiled. Depending on the place in the sequence of elements of a multistage cleaning system, the life of such a filter can be from a few months to several years. Replacement elements are usually inexpensive, so they are often used as the first stage of purification – with or without prefilters.

Many brands are equipped with HEPA filters: Air Comfort, Ballu, Boneco, Bork, Dantex, Panasonic, Sharp, Timberk and several others.

To clean the air from dust and some allergens are widely used

and electrostatic filters

. The principle is based on the physical property of charged particles to attract to objects with an opposite charge. When the air enters the device, the dust particles it contains are first electrified and then adhere to a special plate with an opposite charge.

There are a lot of cleaner models on the market with such filters, because they are inexpensive, easy to use and do not require changing: you only need to occasionally remove the plate with dust adhered to it and wash it in water. The electrostatic filter can function as a single filter stage or work “alone” – without other elements.

Though HEPA and electrostatic filters are highly effective in cleaning the air from mechanical pollution they cannot provide protection from volatile compounds – odors and gases. Other types of filters are used to combat these phenomena. Perhaps the most common of these are

– charcoal

.

Activated carbon is known to be an excellent sorbent and has been designated as a deodoriser in air-cleaning systems: it absorbs odours and many types of chemicals. Charcoal filters tend to clog up and lose their quality over time, so they must be periodically replaced with new ones. Some companies offer air purifier models with washable charcoal filters: rinsing them prolongs their life. Carbon filters are available in ranges of most major manufacturers of air cleaners.

In recent years the use of negative ions has become more and more widespread

photocatalytic filters

. Their action is based on the ability of some photo-catalyst substances e.g. titanium dioxide to oxidize and destroy chemical molecules, odors, as well as viruses, bacteria, fungal spores and a number of other harmful organic pollutants.

The effect is intensified under the influence of ultraviolet, so photocatalytic filters are often supplemented with an ultraviolet lamp. Filters of this kind are also good because they can be regenerated: under the influence of UV light they recover their oxidative properties. Air purifier models are equipped with photocatalytic filters. Air Comfort Ballu, Daikin, Panasonic, Timberk, “Atmos.

Other filters. Other filters can also be used for disinfecting the air. Widespread are versions based on different plant extracts e.g,

catechins

– you can often find them on the market of air purifiers . Filters containing silver are effective and popular. Additional antibacterial effect gives also ozonization of the air.

The service life of this or that filter type depends partly on the order in which the filter stages are located inside the filter. To take some of the load off the main filtering elements many manufacturers equip air purifiers with prefilters. They are usually made of a grid that traps the bigger dirt particles dust flakes, animal hair, etc. . p. , which speeds up the clogging of finer filters.

Many models support additional functions. So, some of them can humidify the air besides cleaning they have special water tanks . There are even devices with fragrance function.

Ionization

It is known that negatively charged ions have a positive impact on human health. It is not without reason that after thunderstorms or near water reservoirs and waterfalls, people feel more energetic and feel better to breathe. But in city air – and especially indoors – the saturation of negative ions is extremely low. Negative ions outnumber the positive ones and are not sufficient to have a positive effect on the body. That is why air purifier manufacturers often equip their models with ionizers – these small devices generate negatively charged ions.

Ions also play an active role in the air purification process in addition to their positive effects on the body. So, they are able to charge the dust particles that begin to adhere to each other and form larger particles. In this form they are better detained by filters.

Many manufacturers’ air purifiers are equipped with ionizers of different action: AIC, Ballu, Boneco, Bork, Daikin, Dantex, Panasonic, Sharp, Timberk, “Atmos”.

a more sophisticated and effective cleaning technology using ionization involves the use of both positively and negatively charged particles. The device splits the water molecules to form free positive hydrogen ions and negative oxygen ions.

They interact with the water molecules in the air and form clusters of ions which are converted to hydroxyl radicals OH-. These radicals surround microorganisms and chemical molecules and take hydrogen atoms from their structure, resulting in the death of bacteria and viruses as well as deactivating odors.

This technology of ionization and cleaning is different in that it deactivates harmful microorganisms directly in the air, rather than in the body of the device. In addition, bipolar ionization restores the balance of ions of both charges in the room, preventing an overabundance of negative or positive charged particles. A similar technology Plasmacluster is used in the models of Sharp.

Water instead of filter

The so-called air washers are an alternative to traditional multi-stage purifiers. The filtering element in these devices is ordinary water.

The washing principle is simple: a fan draws air into the cabinet where it passes through a rotating drum of water. Contaminant particles in the air are wetted and remain in the water, and the purified air flows back into the room.

An important feature of sinks is that they not only clean but also humidify the air effectively. During their operation, the water evaporates from the tank and increases the humidity level to a comfortable 40-60% which is especially important in winter, when the heating system causes the humidity to drop and the dry air to be uncomfortable .

A significant advantage of sinks over traditional filter air purifiers is that sinks do not require filter replacement.

The contaminated water is poured out, the container is washed, clean water is poured – and the air washer is ready for use again.

The exception is the models of air washers with different additional cleaning elements, for example, with disinfecting water with antibacterial silver rods Electrolux has them in its line of sinks .

However, sinks are able to trap particles larger than 10 microns, while smaller ones are not wetted and can pass through the water barrier and back into the room. Sinks do not remove odors and gases as well. Therefore, their degree of purification is lower than that of purifiers with fine filters and various chemical absorbing filters.

In the American market air washers presented brands Ballu, Electrolux, Timberk, Venta, etc.

Operation

Air purifiers are usually unpretentious: they do not require special installation or any special maintenance conditions – unlike the air conditioners. Taking care of them comes down to replacing filters on time or cleaning them if they are washable . Some models even have indicators to tell you when the filter needs replacing or cleaning.

As a rule, filters are bought at the same place where you buy the air-cleaner. The process of replacing them is simple and does not require special skills.

Often manufacturers form from several filters a single unit, which can be replaced at once the whole – so as not to bother with each specific element.

You should not neglect maintenance of filters. Firstly, dirty filters reduce the efficiency of air cleaning and decrease the productivity of the device.

Secondly, the accumulated dirt can harbor harmful microorganisms which will easily get into the room with the air flow coming out of the air-cleaner

Air cleaners are usually placed on the table or on the floor, and the latter option is even more rational – after all, settling dust particles accumulate near the floor. The place for the cleaner is better to choose an open one – such that the objects of furniture do not interfere with the appliance freely take in and blow out the air.

Most models of purifiers are able to work around the clock many of them even have a quiet mode for night time – so they do not disturb people’s sleep with their noise .

And it is recommended not to turn appliances with humidifying and air washing function at all – after all, the appliance has to work all the time to keep the humidity at a certain level. By the way, the intensity of water evaporation can be increased by placing the sink or cleaner closer to the heaters.

Air purifiers are usually compact enough to allow you to move them from one room to another, some even have a special carrying handle. Mobility is an important advantage of these devices compared to, for example, split-systems with air cleaning functions: the last ones are firmly mounted to the wall and one cannot carry them in any other room.

The airing myth

There is a common opinion that if the air purifier works in the room, you can leave it unventilated. After all, the quality of the air increases – it becomes cleaner… But this is not true. Air purifiers can protect against harmful substances, germs, and mechanical contaminants. But they can not compensate for the loss of oxygen in the air. Therefore inflow of fresh air from the street is necessary if, of course, ventilation in the house does not solve this problem even without open windows .

But everything is good in moderation. If you have constantly open windows in the room, you will hardly succeed in purifying the air inside the room – constantly arriving masses of fresh air will force already purified air out of the room and the air purifier will work practically idly, wasting the life of filters.

A somewhat similar situation is observed with humidification. In order to keep the humidity at the right level, not only the windows but also the doors must be closed in the room. Otherwise, the steam will spread all over the apartment, and to maintain a comfortable humidity in such a large area model, designed for a smaller load, will simply not be able to.

Subtlety

Some models of air purifiers are equipped with sensors that respond to the level of air pollution and even to many pungent odors, such as tobacco smoke. Such sensor allows the device to register the deterioration of air quality and automatically switches to a more intensive mode of cleaning – all without human intervention.

Sensitivity sensor, as a rule, can be adjusted to your own preferences – for example, reduce it so that the sensor does not trigger too often, forcing the cleaner to make more noise especially at night