The 2 main reasons to get an air purifier for your home

Do you really need an air purifier to improve the indoor air quality in your home? Humans managed to exist for hundreds of thousands of years without them, so are air purifiers actually necessary? Well, to be fair, since the Industrial Revolution started in Europe a couple of hundred years ago, the air we breathe has been increasingly contaminated with the by-products of manufacturing, growing populations and modern living.

Despite this, an air purifier isn’t really an essential item for a lot of us - although that’s not to say it’s not a nice device to have in your home. If you suffer from allergies or respiratory issues like asthma, though, or if you live in an area with high levels of pollution or irritants, this home appliance could help you breathe more easily and enjoy life without the discomfort of sneezing, burning eyes and itchy skin.

You can think of an air purifier as a vacuum cleaner for the air in your home. It works by sucking the air in and trapping dust, pollen, mould spores, pet dander (dandruff), germs and smells, before cycling the cleaned air back into the room.

Wait a minute: don’t air conditioners also clean air while they’re chilling it? Unfortunately not. While the filters on air con units can trap some airborne dust, they don’t really filter out other contaminants to improve indoor air quality. This is because air conditioners operate at a greater intensity, with the air moving through the system at too great a speed and volume to be cleaned by dense HEPA air purification filters.

A lot of air purifiers will have other, secondary air filters in addition to the HEPA filter, to target the allergens, odours or germs that the HEPA may not capture. These include carbon, ionic and ultraviolet (UV) filters.

Activated carbon filters use a charcoal screen to trap pollutants like bushfire and tobacco smoke, gases and airborne chemicals known as volatile organic compounds (VOCs) from household cleaning products, furniture and paint. However, they don’t capture allergens and bacteria, so are often used alongside HEPA filters in air purifiers, sometimes as ‘pre-filters’.

Ionic filters (aka ionizers) are less effective overall than HEPA filters, but are efficient at capturing the very smallest particles. Unlike HEPA and carbon filters, which use physical filtration systems, ionic filters generate electrically charged ions to neutralise pollutants, allergens and smells. The ions attach themselves to microscopic particles in the air, making them heavy and causing them to fall to the ground or be drawn back to the air purifier to be captured by special plates.

Like the ionic filter, ultraviolet filters don’t physically capture pollutants in the air, rather they emit UV light, which has a wavelength that kills viruses and bacteria. Ineffective against allergens, smells and smoke, their ability to destroy bacteria and microbes and improve indoor air quality makes this type of filter popular in hospitals and other medical settings.

Ozone filters produce ozone gas, which neutralises smells, but does not remove allergens or pollutants. It’s worth noting that ozone can be harmful in high concentrations, and there has been a move away from using them in the home, with some air purifiers now touting their ‘ozone’-free credentials.

While effective at improving air quality, there is no conclusive evidence that air purifiers, even those with ionic filters, are able to kill COVID-19 coronavirus.

You will generally need to replace the filters for HEPA air purifiers every 6-12 months, because they cannot be cleaned. If you were to have a standalone ionic or UV light purifier, you wouldn’t need to replace any filters - but these would have limited effectiveness in terms of cleaning the air. Replacement HEPA, carbon and combination filters vary in price, but often cost between $50 and $200.

For some air purifiers, you can clean larger particles like pet hair and dust from the pre-filters. Some of these pre-filters can be vacuumed, while others can be washed, so always check the manual that comes with the unit for any specific instructions about both cleaning and replacement (Appliances Online includes the manual for each product on the website where possible, so you can check the details out before you buy). Because they are the ‘first line of defence’, pre-filters tend to need more regular cleaning (i.e. monthly) and replacement (i.e. quarterly).

You may want to clean all of the air in your home equally, or you may want to focus on specific areas, such as an asthmatic child’s bedroom, or a kitchen-dining area. If you want to purify the air throughout a house, you will likely need multiple devices, but this may vary if you have a more modern home with open-plan design and fewer doors and walls.

Most air purifiers will be able to clean the air in a regular sized room, but some will have the capacity to clean larger, open plan spaces. The size of room that they are capable of cleaning will usually be stated on the appliance’s specifications. Before you shop, establish the size of the area that you want to target by multiplying the length of the room by its width to give you its area in square metres.

If you want to maximise the purity of the air in your home, you will probably want to keep your air purifier running 24/7. It sounds energy-intensive, but modern air purifiers actually have very low power demands, of between 20W and 60W, which is less than a lot of lightbulbs, so keeping it running continually won’t be too expensive. It’s worth noting that the filter replacement times given for most air purifiers is based on the air purifier running continually, but if you were to only run a purifier in a bedroom at night, for example, then the filter’s life may potentially be extended.

It’s best to place your air purifier a few feet off the ground, on a table or cabinetry, but not too high up. Corners should be avoided because having a wall on two sides can impede airflow. The aim of the purifier is to improve the quality of the air that you’re breathing, so it’s ideal to have it located close to where you spend most of your time in a room. In a bedroom, this might be a bedside table. In a living room it might be closer to the sofa. The purifier can clean the air throughout the room, but closer proximity to it will mean that you’re breathing purer air that’s just been cleaned.

Alternately, if you want to target specific source of pollutants or odours, such as gases and particles produced during cooking, then it makes sense to position the purifier unit closer to this area.

Fair question, because these devices often get grouped together. In a nutshell, air purifiers clean the air, whereas humidifiers put moisture into the air and dehumidifiers take moisture out of the air.

You might want to use a humidifier in dry conditions, when low humidity can dry out mucous membranes in the nose and throat, leading to colds and respiratory infections, especially for babies and small children. By adding moisture to the air, it can also prevent problems like dry skin and chapped lips.

A dehumidifier, on the other hand, sucks moisture out of the air when the humidity is too high. High humidity can cause mould and dust mites, both of which can aggravate asthma and allergies.

The National Asthma Council of Australia states that indoor humidity should ideally be between 30-50%. Below this range might prompt you to use a humidifier, and above it a dehumidifier.

So, there are times of the year you may need to use either a humidifier or dehumidifier - but neither of these devices clean the air, so if you’re looking to reduce allergens and air pollutants year round, you’ll need an air purifier.

The best type of air purifier you can get will be one with the most advanced filtration technology, which will be a combination of HEPA and other filters. At the higher end of the price range (around $1,000), you’ll find air purifiers with a vast array of features and settings, from super-filtration and silent operation, to minimal energy use, patented airflow and antibacterial technology and a higher clean air delivery rate (CADR). You don’t have to spend big to get a good air purifier though: more basic, but still effective, models start from a couple of hundred dollars.

Whether you buy a cheaper or higher end air purifier, you’ll also have the ongoing cost of replacement air filters. If dust particles and indoor air pollution are adversely affecting your everyday health and wellness, however, this will be a small price to pay to breathe more easily.

We deliver air purifiers, and the rest of our products, to 95% of Australia’s population with Appliances Online's legendary FREE delivery - and we can usually get it to you by the next day (Mon-Fri). Most Australian retailers don’t offer this, so if you’re comparing prices you should factor in the delivery cost and how long it will take to get delivered. PLUS, if you’re getting rid of an old appliance, we can even collect it and take it away for recycling when we deliver your new purchase. Nothing’s too big or bulky for our teams, whose strength is as legendary as their smiles!

You can check out the full range of air purifiers, or if you want a bit more advice on choosing the best type or size for you, read our Air Purifier Buying Guide or call our friendly team 24/7 on 1300 004 500 if you have any questions.