Pug sits next to large air purifier

A breath of fresh air: Your air purifiers buying guide

Published 27th January 2023
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Are you tired of breathing in stale, stuffy air in your home? Are you tired of sneezing and coughing every time you step inside? An air purifier could be the answer! These powerful devices are like a personal air cleaning system for your home, working tirelessly to remove pollutants and particles that can cause allergies, asthma and other respiratory issues.

But with so many options on the market, it can be overwhelming to choose the right one for you. That's why we've put together this buyer's guide to help you navigate the world of air purifiers and find the perfect fit for your home. So, let's take a deep breath and dive in, because fresh, clean air is just a few clicks away!

What is an air purifier?

We might think that the air in our homes is pretty clean, but actually it's a lot dirtier than we might think. There are several types of air pollutants that can appear in the home, each with its own specific causes.

Some of the most common include dust, mould, pet dander and pollen, all of which can cause allergic reactions or make conditions like asthma worse. Viruses and bacteria also count, although we often don't think of them as pollutants because they aren't chemicals.

You've probably heard of these but less famous home air pollutants include volatile organic compounds (VOCs), which are given off by household products like paint, cleaning supplies, and air fresheners. VOCs can cause a range of health issues, including headaches, dizziness and respiratory (breathing) problems.

Air purifiers can help that! An air purifier is basically a fan that's attached to a filter. The fan draws air from around the room through the filter and the filter cleans it. The air then naturally cycles back into the room from the fan's momentum.

Different types of air filters, explained

The filter is perhaps the most important part of an air purifier, since it's what actually filters the air. There are many different types of air purifiers available on the market today, and they don't all catch the same pollutants. Here are some of the most common:

HEPA (high-efficiency particulate air) filters

HEPA filters are considered essential as they're what catches allergens like pollen, dander and mould. They can trap up to 99.97 percent of airborne particles down to 0.3 microns in size (that's 0.0003mm across). They are usually made up of multiple layers with each layer designed to capture different sizes of particles.

Activated carbon filters

Activated carbon filters are designed to absorb gases such as VOCs from the air. They are usually made up of activated charcoal which has been treated with oxygen or steam to open up millions of tiny pores on its surface that can absorb gas molecules from the surrounding environment. They also help to remove unpleasant odours like smells from burnt food or tobacco smoke.

UV light filters

UV light filters use ultraviolet radiation to destroy airborne pollutants like viruses and bacteria before they enter your home or office space. UV filters are especially effective at reducing levels of mould spores in the air.

Ionising filters

Ionising filters release negatively charged ions into the surrounding environment, which attach themselves to airborne particles (like dust and pollen) before settling onto surfaces. These particles can then be easily removed with a vacuum cleaner or damp cleaning cloth. They are particularly useful for people with allergies, as they can reduce airborne allergens without releasing any chemical agents into the environment.

The best air purifiers combine one or more of these filters to tackle different pollutants. For instance, a combination of high quality HEPA filters and UV light filters can help to reduce the number of viruses in the air. Make sure to check the product description to find out what filters the purifier you're interested in uses.

Air purifiers & size

With air purifiers, size matters. Some purifiers are small enough to rest on a bedside table, while others are almost as big as a bedside table! So, how do you know if the air purifier you're considering is large enough for the space it's intended for?

First, consider the square footage of the room. Most air purifiers will have a coverage area listed on the packaging or in the product description, so you can compare it to the size of the room. A general rule of thumb is to choose an air purifier with a coverage area that is at least two times the size of the room.

Another factor to consider is the air exchange rate, which is the number of times the air in a room is completely replaced per hour. A higher air exchange rate is better for larger rooms or for rooms that regularly fill with pollutants, such as your kitchen. The last thing is to consider the purifier's CADR rating. But what is that, exactly?

CADR ratings, explained

CADR (which stands for clean air delivery rating) is a rating system used to measure the effectiveness of an air purifier. It measures how quickly the air purifier can reduce smoke, dust, and pollen particles from the air. The higher the number, the faster the air purifier can clean the air in a given space. When shopping for an air purifier, make sure to check its CADR rating so you know how well it will work in your home or office.

Other air purifier features

Air purifiers come with a variety of secondary features that can make them even more convenient and effective at cleaning the air in your home.

One popular feature is the ability to connect to a smartphone app, allowing you to control the purifier remotely and even set schedules for when it should turn on and off. This is a great option for those who want to ensure their air is always being cleaned, even when they're not home.

Another feature to look for is a built-in air quality sensor, which can detect the level of pollutants in the air and adjust the purifier's settings accordingly. This ensures that your air is always at its cleanest, without you having to constantly monitor it yourself.

Noise level is also an important consideration when choosing an air purifier. Some models are designed to be ultra-quiet, making them perfect for use in bedrooms or other spaces where you want to keep noise to a minimum.

Additionally, you can find air purifiers which can be controlled through your voice, usually via a connected smart speaker. This feature can often be combined with the smartphone app and other smart home appliances: You can create customisable instructions for different appliances that trigger one after the other with a single voice command.

Other features to look out for are a night mode that dims the lights and reduces noise, and even a built-in humidifier for added moisture in the air.

Air purifier brands

There are air purifier models made by a ton of brands, from clean-air specialists to famous tech titans. Let's take a look as some of the more popular air purifier manufacturers:


How much does maintaining an air purifier cost?

The cost of maintaining an air purifier depends on how often you use it and how often you need to replace its filters or bulbs (for models that use UV light). Generally speaking, replacing filters every 3-6 months is recommended whilst bulbs should be replaced annually (or sooner if they become dim). However, manufacturers might suggest a different time frame, and it's best to follow their advice for any particular model.

How else can I improve my home's air quality?

To make your air purifier even more effective, here are some simple things you can do to improve the air quality of your home. First, you can start by opening your windows and doors regularly to let fresh air circulate. This is a great way to bring in some natural air and get rid of any stale air that's been trapped inside.

Another way to improve air quality is by keeping your home clean and free of dust and clutter. Regularly dusting, vacuuming, and mopping can help remove pollutants from the air and prevent them from building up. If mould and damp are a concern, then you should invest in a dehumidifier (or buy an air purifier with a dehumidifier built-in), since mould does not like dry air.

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