Last updated on 01/06/2021

An air purifier is something to consider before the air gets bad.   

Air purifiers became a hot ticket item in 2020, when bushfire smoke leached into our homes and workplaces.  A major trigger of asthma, the toxins in smoke poses a serious risk to our health, and air purifiers, when selected carefully and used correctly, are one way we can keep the air inside our homes safe.  

The right sort of air purifier can help with cleaning inside air from nasty triggers like fine particulate matter found in smoke (PM2.5), dust, microbes, and other volatile organic compounds.  

We caught up with CHOICE recently to discuss the ins and outs of air purifiers, you can watch that here. 

Here are a few tips from our chat with CHOICE to think about:  

It’s all in the filter

The best filter to look out for in an air purifier is the HEPA filter. That is an extremely, densely woven material that when air is blown through it containing dust or smoke, it’s almost impossible for those particles to make it through. HEPA filters catch about 99.95% of particles sized down to smaller than a micron.  

Air purifiers have an important role to play in improving indoor air quality related to a range of substances that can trigger asthma. For people with asthma, this can be beneficial for making your home a safe place to be.    

What should I expect to pay? Size counts.

Buying them is relatively easy, most appliance stores stock them.  However, when air gets bad like bushfire smoke, they may become an unexpected expense that you hadn’t budgeted for. It’s better to plan for your purchase, so you don’t get caught out. 

The prices may range between $300 to $500.  Keep in mind that paying top dollar doesn’t guarantee you’re getting the best model.  

CHOICE tended to find that the bigger the model, the bigger the fan, the bigger the filter, and the bigger the air space it can clean, more quickly.  This is important if bushfire smoke gets inside. It is important to note that the smaller models may lack the oomph to be effective. Models should be large enough to be floor standing units. 

Most air purifiers have a room rating size.  It will give you a guide for your room.  

You want a good range of fan speeds, which ramp up to help clear out trapped smoke quickly at peak periods, and down to a gentle fan for while you sleep at night.  

The ongoing cost of air purifiers – making the filter last

Something to really consider is the replacement of filters. You can’t wash or reuse a HEPA filter.  They will last a long time, but they will eventually clog up.  Good units will often alert you when it is time to replace the filter.    

Check what it costs to replace the unit’s HEPA filter and its lifespan, before purchasing a model.  It can add up to a couple of hundred dollars a year. So, it’s an important factor and may help you decide one over another 

If you’re using the air purifier a lot, then naturally it will use up the filters faster.  It may be worth your while investing in a longer-lasting filter system. 

How much air can they clean and what about the noise?

It’s a little bit like an air conditioner, you have to think about the room and capacity of the unit.  If you have a large living room and bedrooms, you may like to consider a big unit for the living area and smaller units for the bedrooms. Many are portable, and you can move them around the house.  

The big units can be noisier, and the noise is something worth considering if you’d like it in your room at night. A smaller unit can be better for sleeping. 

Cooking is a source of pollutants and irritants in the air.  Gas cooktops produce irritants and smoke from food can irritate sensitive airways. It’s something to think about when purchasing a unit, where you will use it, and what the indoor sources of air pollution are. The use of an effective extraction fan over your cooktop and good room ventilation (open windows) is one of the most effective ways to reduce indoor air pollution from cooking. 


Prevention is key

Going into the cooler months, it’s important to make sure your asthma is well-managed. For most people, this means having had an asthma review, getting an updated written Asthma Action Plan, and taking your preventer medication as prescribed even when you are feeling well. Read more about how to breathe better in cold weather here and take a few steps to asthma management. 

If any of the above triggers impact you or someone who you care for, ensure you speak with your doctor on how to manage your asthma when smoke is present and take all the necessary steps to prevent asthma flare-ups and/or attacks. Ensure people around you are aware that you have asthma, and where possible have taken a refresher in Asthma First Aid. 

Stay up to date with air quality in your area

The AirSmart App provides live air quality information so that you can change your plans if pollution levels are high.

If you have asthma, this app is especially useful to plan your day or understand why you might be getting symptoms.

Be prepared for an air-quality event

If your area is known to experience winter fires, or there is smoke around, make sure your home is ready. 

Have your medicines and supplies in place, including P2 or N95 masks if conditions are likely to be severe and/or prolonged. Cloth masks or surgical masks are not adequate protection against air pollution.  

Additionally, an air purifier can help to improve the quality of the air inside your home. Think of an air purifier as one of several measures you can take to avoid exposure to allergens and irritants, which can be helpful in managing your asthma. However, these appliances vary in effectiveness, so make sure you check whether the product is the right one for you. View CHOICE’s latest air purifier product testing report here. 

Check if your home windows and doors are sealed. If not, it is recommended to repair them or consider how to reinforce them to reduce their leakiness if you know there is pollution around. You might also create a clean air shelter in your home. This is a space small enough where air quality can be maintained and air pollution is minimised, so you and your loved ones are less exposed, until conditions improve. Air purifiers can be effective in maintaining air quality in such spaces.   Air conditioning can also be effective in these spaces for short periods of time. Set the air-conditioning to recirculate, so the same air is used instead of outside air. 

If air quality continues to worsen, you may like to go to a community refuge, like a shopping centre, library or cinema where air quality is provided for a longer period of time.  

Tell others and make plans if necessary

If you know an air-pollution event is coming, let other people know you or a loved one has asthma.  

Make sure your child’s school has their updated Asthma Action Plan and knows how to manage it. For adults, discuss the events with your workplace and consider other work or travel arrangements if possible.  

It’s best to have a plan in place so you know what you need to do when you need to do it and ensure those close to you have taken a refresher in Asthma First Aid and know what to do in the case of an emergency. 

We’re here to support you

If you are unsure about how to manage your asthma in a situation of air pollution, you may like to call 1800 ASTHMA (1800 278 462) and speak with one of our Asthma Educators. 

We also have a range of detailed resources via our website.

Information provided here and within this video interview does not replace professional medical advice. People should ask their doctor any questions about their asthma, diagnosis, and treatment. People who are experiencing difficulties with their asthma can call an Asthma Educator on 1800 ASTHMA (1800 278 462) for free confidential phone support and information or should visit their doctor. In an emergency, always call triple zero (000). 

Additionally, Asthma Australia does not endorse any individual product taking the approach asthma is a complex chronic health issue and every individual has different health needs, please refer to the Product Endorsement Policy