Wildfire Smoke in Ontario: 10 Things to Do When the Air Turns Severe (Kids, Older Adults, Everyone)

A few summers ago I stood on a Toronto sidewalk at noon and the sun was a dull orange disc. The air smelled like a campfire that never ended. My phone buzzed with a Special Air Quality Statement, and the AQHI — the Air Quality Health Index — had climbed into double digits. The fires were hundreds of kilometres away, but the smoke didn't care about distance.

Since then, wildfire smoke has become a recurring part of Ontario summers. Not every year is severe, but enough of them are that every family here should have a plan. This is that plan — practical, calm, and specific.

If you want to see how connected this is, I built a live 3D globe of active wildfires and air quality worldwide. On a bad smoke day you can watch the fires burning across Canada and the plumes drifting over the places people live. It's sobering — and it makes the abstract very real.

First, understand the number that matters: the AQHI

In Canada we don't use the US-style AQI as our primary guide — we use the Air Quality Health Index (AQHI), from Environment and Climate Change Canada. It runs from 1 to 10+, and it's designed around health risk, not just pollutant concentration.

1–3 — Low risk. Normal activity is fine.
4–6 — Moderate. At-risk people should consider easing up on strenuous outdoor activity.
7–10 — High. At-risk groups should reduce or reschedule outdoor exertion; everyone should take it easier.
10+ — Very High / severe. Everyone should avoid strenuous activity outdoors. At-risk people should stay indoors.

During the worst smoke events, Ontario cities have seen the AQHI blow past 10 into "off the chart" territory. That's the level this guide is written for.

The check-it-yourself sources: the WeatherCAN app, Environment Canada's AQHI page, and your local Special Air Quality Statements. For the big picture — where the fires actually are — my wildfire globe pulls live data from NASA's satellites.

10 things to do when the air turns severe

1. Check the AQHI before you plan your day

Make it a habit, like checking the temperature. If it's 7 or above, the plan changes. If it's 10+, the plan is stay in.

2. Close up and recirculate

Shut windows and doors. If you have central air or a heat pump, set it to recirculate so it isn't pulling smoke inside. On a hot day this is a real trade-off with heat — prioritize based on who's home and how vulnerable they are.

3. Run a HEPA air purifier — or build one

A true HEPA purifier sized for the room makes a measurable difference to indoor PM2.5. No purifier? A Corsi-Rosenthal box — a box fan taped to four furnace filters (MERV 13) — is a cheap, genuinely effective DIY option that got a lot of Canadians through recent smoke seasons.

4. Wear a well-fitted N95 or KN95 outdoors

This is the one people get wrong. Cloth and surgical masks do not filter wildfire PM2.5. You need a proper N95/KN95 with a good seal around the nose and cheeks. If you must be outside during a severe event, wear one.

5. Create one clean-air room

You don't need to purify the whole house. Pick one room — usually a bedroom — close it, run the purifier there, and make it the place everyone retreats to, especially for sleep.

6. Set your car to recirculate

Driving through smoke? Windows up, ventilation on recirculate, AC on. Many newer cars have a cabin air filter — a good one helps.

7. Cancel the workout, the run, the yard work

Exertion means deeper, faster breathing — you pull more smoke deep into your lungs. Move workouts indoors (in filtered air) or skip them. This isn't the week for a personal best.

8. Keep rescue medications close

If anyone in the house has asthma or COPD, make sure inhalers and prescribed medications are stocked and within reach, and review the action plan before symptoms start.

9. Watch for symptoms — and know the red flags

Mild: scratchy throat, irritated eyes, runny nose, mild cough. Take those as signals to get to cleaner air. Red flags — chest pain, severe shortness of breath, wheezing that won't settle, dizziness, or heart palpitations — mean call your doctor, Telehealth Ontario, or 911. Don't tough those out.

10. Check on the vulnerable — including neighbours

Older relatives, people with heart or lung conditions, families with newborns, anyone without air conditioning or a purifier. A phone call or a spare box-fan filter can matter more than you'd think.

The impact isn't the same for everyone

Wildfire smoke is mostly fine particulate matter (PM2.5) — particles small enough to travel deep into the lungs and into the bloodstream. But who it hurts, and how, varies a lot.

For kids

Children breathe faster than adults and take in more air relative to their body size, so they absorb proportionally more smoke. Their lungs are still developing. On severe days:

Keep outdoor recess and sports indoors — and ask whether the school is doing the same.
Watch for coughing, wheezing, or a child who's unusually tired or short of breath.
For kids with asthma, be extra proactive with the action plan; smoke is a common trigger.
Babies and toddlers can't tell you they feel unwell — err on the side of caution and keep them in filtered air.

Help them understand it, gently. Kids fear what they don't understand, and a smoky orange sky is genuinely unsettling for a small child. A calm bedtime story does what a lecture can't — our kids' storytelling venture, My Sleepy Tale, just released an audiobook for kids, "When the Sky Turns Orange", where a gentle doctor explains smoky skies and how to keep little lungs safe. Let them listen, then explore the live 3D wildfire globe together to see where fires are burning around the world.

For older adults

Adults over 65, and anyone with heart disease, high blood pressure, or lung conditions, are the highest-risk group. Smoke doesn't just irritate lungs — it stresses the cardiovascular system, and severe smoke days are associated with more heart attacks and strokes.

Stay indoors in the clean-air room during high and severe AQHI.
Keep taking regular medications; don't skip doses.
Stay hydrated, and don't dismiss symptoms as "just the smoke" — chest tightness or breathlessness deserves a call to a professional.

For healthy adults

You're the most resilient group, but "healthy" doesn't mean immune. On severe days even fit adults get headaches, sore throats, burning eyes, and fatigue.

Reduce strenuous outdoor activity when the AQHI is high; avoid it entirely at 10+.
If you're pregnant, treat yourself as an at-risk group — reduce exposure.
You're also the one who sets up the purifier, fits the kids' masks, and checks on the older folks. Being the calm, prepared adult is the job.

The bigger picture

Wildfire smoke used to feel like someone else's problem — the West Coast, the far North. It isn't anymore. A fire in northern Quebec or Ontario can put Toronto, Ottawa, and half the northeastern continent under a haze within a day.

That's exactly why I find the live wildfire globe so compelling to look at during a smoke event: you can filter by country, watch Canada's active fires in real time, and see the air-quality readings light up around the world. It turns a scary, invisible thing into something you can actually understand — and understanding is the first step to being prepared.

Stay safe out there. Check the AQHI, keep an N95 in the drawer, and know your clean-air room. When the sky turns orange again — and it will — you'll be ready.

This guide is general information, not medical advice. For personal health concerns, follow guidance from Health Canada, your local public health unit, and your doctor.