Bushfire season is an annual reality for Australians, and with changing climate patterns, the intensity and duration of fire seasons have been increasing. Even if you're hundreds of kilometres from active fires, bushfire smoke can travel vast distances, affecting air quality across entire states. The Black Summer fires of 2019-2020 demonstrated how smoke could blanket cities for weeks, turning day into an eerie orange twilight.
Protecting your indoor air quality during bushfire events isn't just about comfort—it's a genuine health concern. This guide will help you prepare your home and family for smoke events, understand the health risks, and take practical steps to breathe easier during fire season.
Bushfire smoke contains fine particulate matter (PM2.5) that can penetrate deep into your lungs and enter your bloodstream. People with asthma, heart conditions, respiratory diseases, the elderly, pregnant women, and young children are at higher risk. If you experience difficulty breathing, chest pain, or severe symptoms during smoke events, seek medical attention immediately.
Understanding Bushfire Smoke
Bushfire smoke is a complex mixture of gases and fine particles produced by burning vegetation and other organic materials. The most concerning component is particulate matter, particularly PM2.5—particles smaller than 2.5 micrometres in diameter. These tiny particles are so small they can bypass your nose and throat and lodge deep in your lungs.
The health effects of smoke exposure can be immediate or develop over time with repeated exposure. Short-term effects include irritated eyes, runny nose, coughing, and difficulty breathing. For people with pre-existing conditions, smoke exposure can trigger asthma attacks, heart palpitations, and severe respiratory distress.
What's in Bushfire Smoke?
- Particulate matter (PM2.5 and PM10): Fine and coarse particles that damage lungs
- Carbon monoxide: Reduces oxygen delivery in the body
- Volatile organic compounds: Can irritate airways and eyes
- Nitrogen oxides: Respiratory irritants
- Polycyclic aromatic hydrocarbons: Some are known carcinogens
Preparing Your Home Before Fire Season
The best time to prepare for bushfire smoke is before fire season begins. Taking steps in advance ensures you're ready when smoke events occur, rather than scrambling to find solutions when air quality deteriorates.
Seal Your Home
Smoke finds its way into homes through every gap and opening. While you can't make your home completely airtight (and wouldn't want to for normal living), you can reduce infiltration significantly:
- Install weatherstripping around doors and windows
- Seal gaps around pipes and electrical outlets that penetrate exterior walls
- Check and repair any cracks in walls or around window frames
- Ensure exhaust fans have backdraft dampers that close when not in use
- Consider installing door sweeps on exterior doors
Designate one room in your home as your "clean air room"—ideally a bedroom where you spend many hours. Focus your sealing efforts and air purification resources on this room. During severe smoke events, you can retreat to this space for cleaner air.
Invest in Air Purification
A quality air purifier with a True HEPA filter (H13 or higher) is your most effective tool against smoke particles. When choosing an air purifier for smoke:
- Look for True HEPA: Must capture 99.97% of particles at 0.3 microns
- Include activated carbon: Helps absorb smoke odours and some gaseous pollutants
- Size appropriately: Choose a purifier rated for your room size or larger
- Consider CADR ratings: Higher smoke CADR means faster air cleaning
- Stock extra filters: You may need to replace filters more frequently during smoke events
Position your air purifier in the room where you spend the most time. During sleep, having a purifier in your bedroom is particularly valuable since you're spending 6-8 hours breathing that air.
During a Smoke Event
When bushfire smoke affects your area, take immediate steps to protect your indoor air quality and minimise your exposure.
Monitor Air Quality
Check air quality readings regularly through official sources. Each Australian state has environmental monitoring services that report real-time air quality data:
- NSW: Air Quality Index (DPIE)
- Victoria: EPA Victoria Air Watch
- Queensland: Queensland Air Monitoring
- SA, WA, TAS, NT, ACT: Each has state-based monitoring systems
Pay particular attention to PM2.5 readings. When PM2.5 levels exceed 25 µg/m³, sensitive individuals should take precautions. Above 50 µg/m³, the general population should reduce outdoor activities. During severe smoke events, PM2.5 can exceed 200 µg/m³ or even higher—levels considered hazardous for everyone.
- 0-25 µg/m³: Good—Normal activities for all
- 25-50 µg/m³: Fair—Sensitive groups should limit prolonged outdoor exertion
- 50-100 µg/m³: Poor—Everyone should reduce prolonged outdoor exertion
- 100-300 µg/m³: Very Poor—Avoid outdoor exertion, stay indoors
- 300+ µg/m³: Hazardous—Stay indoors, run air purifiers, seek medical help if symptomatic
Keep Smoke Out
When outdoor air quality is poor:
- Keep all windows and doors closed
- Don't use exhaust fans (they draw air from outside)
- Avoid activities that create indoor pollution (candles, incense, gas cooking)
- If you have ducted air conditioning with fresh air intake, switch to recirculate mode
- Place damp towels at the base of doors if smoke is seeping in
- Run your air purifier continuously on the highest comfortable setting
Protect Yourself When Going Outside
If you must go outside during smoke events:
- Limit time outdoors, especially for physical activities
- Wear a P2/N95 mask—cloth masks and surgical masks don't effectively filter smoke particles
- Ensure your mask fits snugly with no gaps around the edges
- Time outdoor activities for when air quality is better (often early morning)
- Keep car windows closed and use recirculated air mode
P2 (Australian standard) or N95 (US standard) respirator masks can filter smoke particles when properly fitted. However, they're not suitable for everyone—people with respiratory conditions, heart disease, or who are pregnant should consult a doctor before using them. Children and people with facial hair may not achieve a proper seal.
Managing Your Air Purifier During Smoke Events
Your air purifier will work harder during smoke events, and managing it properly ensures maximum protection:
- Run continuously: Don't turn it off when you think the air "seems better"
- Check filter condition: Filters clog faster during smoke events and may need earlier replacement
- Clean pre-filters: If your unit has a washable pre-filter, clean it more frequently
- Don't move between rooms: If possible, dedicate each purifier to one room
- Keep doors closed: Minimise the space the purifier needs to clean
After the Smoke Clears
Once air quality returns to normal, take steps to refresh your indoor environment:
- Open windows to ventilate your home with fresh air
- Replace or clean air purifier filters
- Vacuum with a HEPA-equipped vacuum to remove settled particles
- Wipe down surfaces with damp cloths
- Wash soft furnishings if smoke odour persists
- Check HVAC filters and replace if necessary
Long-Term Considerations
As bushfire seasons become more frequent and intense, investing in air quality preparedness makes sense for all Australian households. Consider upgrading your home's air filtration capability, whether through portable air purifiers or whole-home HVAC filtration systems. Stock up on replacement filters before fire season when demand—and prices—are lower.
For those in high-risk bushfire areas, having a comprehensive smoke protection plan is as important as your bushfire evacuation plan. Know your local air quality monitoring resources, have your supplies ready, and understand how to create the cleanest possible indoor environment during extended smoke events.
Conclusion
Bushfire smoke is an increasingly common challenge for Australian households. By understanding the risks, preparing your home, investing in proper air purification, and knowing how to respond during smoke events, you can significantly reduce your family's exposure to harmful particulate matter. Stay informed, stay prepared, and breathe easier knowing you've taken steps to protect your indoor air quality.