Yesterday, millions of Canadians looked outside and saw an orange sky.

The sun looked red.

The air smelled like smoke, chemicals or burnt plastic.

In Toronto, the Air Quality Health Index reached 10+, the highest risk category used by Environment Canada. Smoke from wildfires in northwestern Ontario pushed air quality into the very high-risk range.

This was not just an unusual looking summer day.

It was a reminder that a wildfire does not need to be anywhere near your home to affect your health or your daily life.

The smoke moved south from wildfires burning in northwestern Ontario.

Across Canada, hundreds of fires remained active, including more than 100 considered out of control. Much of the area burned this season has been in Ontario, Manitoba and Saskatchewan.

For people in southern Ontario, the fires meant orange skies, poor air quality and cancelled outdoor plans.

For communities closer to the flames, the situation was far more serious.

Some northern and First Nations communities faced evacuations as fires threatened homes and transportation routes.

That is an important distinction.

Some Canadians experienced the wildfires as a strange-looking sky.

Others were forced to leave home.

A lot of people described the air as smelling chemical, electrical or like burnt plastic.

That does not automatically mean plastic was burning nearby.

Wildfire smoke contains a mix of gases and extremely small particles. As smoke travels, its smell can change depending on what burned, how far it moved and how it reacted in the atmosphere.

The bigger concern is not the smell itself.

It is the fine particulate matter inside the smoke.

According to Health Canada’s wildfire-smoke guidance, these particles, known as PM2.5, are the main health risk from wildfire smoke because they can travel deep into the lungs.

Smoke can cause coughing, headaches, irritated eyes, a sore throat and breathing problems.

Children, seniors, pregnant people and anyone with heart or lung conditions face a higher risk.

But during very heavy smoke, everyone can be affected.

The simplest step is to check the Air Quality Health Index for your community before exercising, working or spending long periods outside.

Do not rely only on what the sky looks like.

Health Canada warns that air quality can still be poor even when smoke is difficult to see or smell.

When the risk is high or very high:

Keep windows closed where practical.

Avoid strenuous outdoor activity.

Move children’s activities indoors.

Use a portable air cleaner or a good-quality furnace filter.

Wear a well-fitted N95-style respirator when you need to spend time outside.

And pay attention to symptoms.

Chest pain, severe shortness of breath or difficulty breathing should be taken seriously.

Wildfires are often discussed as something happening in remote forests.

But smoke turns them into a public health story.

It closes outdoor spaces.

It affects construction workers, delivery drivers, children at summer camps and people without reliable air conditioning or filtration.

It can also travel hundreds or thousands of kilometres from the flames.

Here’s what people are missing.

Canada is getting better at reacting to smoke days.

We check the air-quality app. We close the windows. We cancel the baseball game.

But we still treat each event like a temporary surprise.

The harder question is whether orange skies and air-quality warnings are becoming a regular part of Canadian summer.

And if they are, are our homes, schools and workplaces ready?

The smoke will eventually clear.

The need to prepare will not.

P.S. What did the smoke smell like where you live, and did it change your plans? Hit reply and tell me what conditions were like in your community.