Lea Bieri , 19.05.2020

Is an air washer or an air purifier better for healthy indoor air?

If you are looking for a device for improving the air quality indoors, you will definitely come across the terms air purifier and air washer – two devices which work in different ways and have different benefits. Both ensure an optimal indoor climate and improve well-being. Air purifiers are designed solely for purifying the air whereas air washers are hybrid devices which have the capacity to clean and humidify the air at the same time. Read on to find out whether an air washer is the right choice for you. Below we explain the differences between air purifiers and air washers and help you to select the right device.

Don’t feel like reading? Then watch the following video which summarises the main points relating to the differences:

Video air purifier vs air washer

What is a good healthy indoor climate?

Awareness of the importance of a healthy indoor climate is growing all the time. Nearly everyone knows that poor air is bad for our health. Thanks to the World Health Organization (WHO), we know that the air indoors is 2 to 5 times more polluted than the air outdoors. Read our blog post entitled «Polluted indoor air: the risk to health» to find out in more detail how indoor air becomes polluted. But what constitutes a good indoor climate? The two most important factors are the relative humidity and how clean the air is. That doesn’t just mean that the air indoors needs to smell pleasant, it also depends on how heavily the air is polluted with particulate and gaseous pollutants. Consequently in order for the indoor climate to be healthy, the air indoors needs to be purified.

Relative humidity of 40–60% is regarded as a pleasant level and is therefore generally recommended. If the humidity is permanently below this value, a humidifier can provide the solution. If the value is permanently above 60%, a dehumidifier can provide relief. This value is measured using a hygrometer. Air pollution can be measured using a range of devices (particle counters, devices for measuring particulate pollution, etc.). As the sources of air pollution vary greatly, that means that different methods of measurement are also required. No matter where you live, the air will be polluted. For besides people themselves who contaminate the air by shedding hair and flakes of skin and emitting bacteria and viruses when they exhale, the outside world also often has a detrimental effect on the indoor climate – both exhaust fumes from vehicles and pollen and dust from outside can filter in and pollute the indoor air. To reduce that pollution, it is worth buying an air purifier or air washer. These two types of device can help you to balance your indoor climate at home by purifying the air.

Air purifiers: how they work and what benefits they offer

Air purifiers have one objective: to remove harmful particles and gases from the air. Particles are removed using a HEPA or electrostatic filter. Gases and smells are removed by means of activated carbon filters. An air purifier needs an activated carbon filter to be able to adsorb smells from the air. Consequently, most air purifiers are equipped with a combination of particulate and activated carbon filters.

Air purifiers suck in the air which is passed over the filters. Dust, allergens, viruses, bacteria, mould spores, smoke, volatile organic compounds and other pollutants are filtered from the air in the process. After it has been purified, the clean air is emitted back into the room.

Air purifiers optimise the indoor air quality significantly which can lead to improved well-being and more restful sleep. For allergy sufferers, purchasing an air purifier often leads to the alleviation of allergy-related symptoms which also leads to a significantly improved quality of life. If an air purifier is also equipped with an activated carbon filter, it will also be able to remove smells such as cigarette smoke from the air. Our air purifiers Roger, Roger little and Viktor are all equipped with activated carbon filters and you can rely on them to remove pollutants from the air – even gases.

In principle, using an air purifier makes sense for anyone who considers healthy indoor air to be important. If the relative humidity in your home is also permanently below 40%, you should look at purchasing an air washer rather than an air purifier.

Air purifier Roger by Stadler Form

The features and benefits of an air washer

The air washer is a hybrid – a 2-in-1 device. Air washers increase humidity while removing pollutants from the air at the same time. The dry and polluted air is sucked in and passed over discs (also referred to a disc pack) turning in water. In the water, not only is the air enriched by absorbing the moisture required but also particles and certain gases are washed from it. The humidified and purified air is then emitted back into the room.

In a dry environment, air washers can create a healthy indoor climate by purifying and humidifying the air at the same time. An air washer can reduce throat irritations, help to add sufficient moisture to dry air or alleviate problems affecting the nasal passages and sinuses and other conditions caused by the air being too dry. An air washer washes particles such as pollen from the air so it can also provide welcome relief for allergy sufferers. It can alleviate allergy-related symptoms which are exacerbated by polluted air and enable sufferers to breathe more easily and sleep more soundly. These 2-in-1 devices can also eliminate certain smells from the air. So air washers ensure better personal well-being and improve vitality.

Graphic disc pack air washer Robert

If breathing clean air at home is important to you and the air inside your home tends to be dry, then an air washer is the perfect solution. With this type of 2-in-1 device – air purifier and humidifier – like our George or Robert, a single device is all that you need for a healthy indoor climate.

We do not recommend that you use an air washer if the relative humidity in your home is always above 50%, even in winter. So if the air inside your home is never too dry, then an air purifier is the right device for you.

A direct comparison of air washers and air purifiers

Comparison table air purifier vs air washer
*= moderate | ** = OK | *** = good | **** = very good | ***** = excellent

Air purification
In a direct comparison, the air purifier is the specialist when it comes to purification and therefore scores full marks. The air washer also performs well when it comes to washing particles and certain smells from the air but doesn’t quite match up to the performance of the air purifier.

The air purifier doesn’t score any points for this because it has no humidification function. The air washer however scores full marks for this because it carries out humidification very efficiently.

Cleaning effort
The air purifier is uncomplicated and very low-maintenance. All you need to do is vacuum the prefilter every now and then and replace the filters every 8–12 months, according to the model in each case.
Cleaning the air washer is a bit more time-consuming as the disc pack and the water tank have to be cleaned at least once a week in order to rinse off the pollutants washed from the air.

Running costs
If your air purifier doesn’t have a washable filter, then there will be regular costs involved in replacing the filter. The recommended service life of a filter will differ according to the model and manufacturer in each case. That is where the air washer has an advantage as the filter medium is water. With our models, the Water Cube – a recommended accessory for improving hygiene but not an integral part of the device – should be replaced once a year.

Have you got any questions on this topic or on our devices? Need advice?
We are always happy to help! Contact us via telephone, e-mail or contact form.

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Comment from Stadler Form at 14.05.2021

Thank you for your enquiry and your interest in Stadler Form products.
Unfortunately, there are no possibilities to purchase our devices in India.
Best regards, your Stadler Form Team

Individual Comment from Jagdish Bhatia at 13.05.2021

Is it avaible in India