What smoke does to your body
The harm comes from fine particles called PM2.5, at least 20 times thinner than a human hair.
They reach deep into the lungs, and the smallest get into the blood. That's why smoke is linked to heart attacks and strokes as well as asthma.
- Short term: sore eyes and throat, coughing, asthma attacks, and heart trouble in people with heart disease.
- Long term: more heart disease, stroke, lung disease and lung cancer.
- Most at risk: people with asthma, lung or heart disease or diabetes, older people, pregnant women and children.
Why Perth gets smoky
From 2002 to 2017, particle pollution in WA broke the national standard on 271 days. Planned burns caused 138 of them. Bushfires caused 59.
- Summer bushfires. Morning easterlies can carry Hills smoke across the suburbs until the sea breeze comes in.
- Planned burns. DBCA burns in autumn and spring. Cool, still mornings keep the smoke low.
- Wood heaters. A big part of Perth's winter haze. Nationally, wood-heater smoke is linked to 558 to 1,555 deaths a year.
- Farm and backyard burning on the city's fringe.
- This summer: a near-record El Niño raises the odds of a hot, dry, smoky season. What it means for Perth.
The numbers
- Black Summer, 2019–20 (eastern Australia): 417 deaths, 3,151 hospital admissions, 1,305 asthma emergencies and $1.95 billion in health costs.
- WA, 2002 to 2017: 41 early deaths and $188.8 million in health costs, half of it from planned burns.
| PM2.5 limit | Australia | WHO (2021) |
|---|---|---|
| 24-hour average | 25 µg/m³ | 15 µg/m³ |
| Yearly average | 8 µg/m³ | 5 µg/m³ |
No level is completely safe. Our live reading uses the US EPA index: 0 to 50 is good, and over 100 affects sensitive groups.
Smoke-day plan
This page prints cleanly. Stick the plan on the fridge.
Before summer
- Fit a fresh purifier filter.
- Pick a clean room, usually the main bedroom.
- Buy P2 masks.
- Check asthma and heart action plans with your GP.
- Bookmark Emergency WA and DBCA's burns list.
On the day
- Close windows, doors and the pet door.
- Turn off the evaporative cooler. It pulls smoke through the house. If fire is close, follow DFES advice on wetting the pads.
- Reverse-cycle air con is fine on recirculate.
- Run the purifier on high in the clean room, door shut.
- No candles, incense, frying or wood fire.
- Skip outdoor exercise.
- Check on older neighbours.
- Can't keep the house clear? Go to a library or shopping centre.
After
- Air the house once the reading is back to good.
- Check the filter after a long smoky spell.
Masks
Surgical and cloth masks don't stop smoke. A well-fitted P2 (N95) mask does.
- It must seal. Beards break the seal.
- They aren't made for children.
- Heart or lung condition? Ask your GP first.
No purifier?
Tape four or five F7 filters (MERV 13 in US guides) into a cube under a box fan. It cleans a room surprisingly well, but it's loud and does nothing for the smell. Don't leave it running unattended.
When to get help
- Call 000 for chest pain, severe breathlessness or collapse.
- Follow your asthma action plan. If the reliever isn't working, it's an emergency.
- Call healthdirect on 1800 022 222 for advice, day or night.
Sources
- Borchers Arriagada N. et al. (2020). Smoke-related health burden of the 2019–20 bushfires. Medical Journal of Australia.
- Borchers Arriagada N. et al. (2020). Exceedances of national air quality standards in Western Australia. Medical Journal of Australia.
- Mortality burden of wood heater smoke in Australia (2024). Science of the Total Environment.
- Australia State of the Environment 2021: air quality.
- HealthyWA: Smoke hazards from bushfires.
- DFES: Evaporative air conditioners factsheet.
- DBCA: Smoke from prescribed burns.
- DWER: Air quality data.
- World Health Organization (2021). Global air quality guidelines.
General information, not medical advice.