Wildfire Smoke Explained: Clearing the Air on Health and Safety

What is Wildfire Smoke?

Wildfire smoke is a mix of tiny solid and liquid particles combined with hazardous gases like carbon monoxide, sulfur dioxide, and ozone. These gases can travel miles from the fire zone and may even reach Earth’s stratosphere, where they can damage the ozone layer.

Wildfires are dangerous, uncontrollable fires that can spring up with little warning and devastate entire acres depending on the climate. But even after the flames die down, the danger isn’t over—because the wildfire smoke that is left behind is also just as dangerous.

Wildfire smoke is extremely harmful to your lungs. It contains ash-like substances called Particulate Matter (PM) such as PM2.5, which are particles with a diameter of 2.5 micrometers or smaller. These are easily inhaled and can impact both your respiratory and cardiovascular systems. Because they’re so small, they can even enter your bloodstream.

This makes it essential to avoid the outdoors during a wildfire and to wear proper protective gear.

How do Wildfires Happen?

A wildfire can only happen when the fire triangle of oxygen, heat, and fuel is complete. Based on this, fuel is anything that can catch fire, like leaves, wood, or even houses. Heat is the fire starter, it makes the fuel hot enough to ignite. Meanwhile,  oxygen is all around us, as it’s the air we breathe. Understanding the fire triangle is key to fire safety, since a wildfire can start unexpectedly whenever all three elements come together.

However, of the three elements, heat is the most critical thing to look out for. Heat can come from many sources. It might be from natural causes, like a lightning strike, or, as in the case of the California fires, extreme heat and drought. But surprisingly, many wildfires are started by humans. In Alberta, Canada, alone, between 2017 and 2022, 68% of wildfires were caused by human activity such as campfires, fireworks, or even firearms.

Climate change also plays a major role in increasing wildfire risk. As global temperatures rise, weather becomes more extreme. In the 2025 LA fires in the US, for example, the landscape was primed for disaster, heavy rains brought rapid growth, followed by extreme heat and record dryness. Add to that the powerful Santa Ana winds blowing down from the Great Basin, and you have the perfect setup for one of the deadliest fires in California history.

All of this shows how important human action is in reducing fire risks and preventing wildfires, whether it’s cutting back on fossil fuels or simply making sure your campfire is fully out.

Differences from Other Types of Smoke

Compared to other types of smoke—like city smog or industrial emissions —wildfire smoke is a mixture of gases and particles that vary depending on what’s burning, such as trees, vehicles, or plastics. When wildfires move through urban areas, they can pick up additional pollutants, creating smoke that’s even more toxic than usual. Advanced smoke control systems, like carbon analyzers or aerosol spectrometers, are used to detect and measure components of wildfire smoke, including light-absorbing aerosols like Black Carbon (BC) and Brown Carbon (BrC), which can heavily impact air quality.

Wildfire smoke also tends to be more visible and dense than urban pollution or industrial smoke. Ash particles from wildfires are more pronounced, these solid, coarser residues are heavier than fine smoke particles and settle more quickly. In contrast, urban smoke rarely contains significant ash unless it includes solid waste or construction materials.

Additionally, research shows that wildfire-related PM2.5 can be up to 10 times more harmful to health than PM2.5 from other sources. This means wildfire smoke can increase levels of tropospheric ozone, a powerful oxidant that can cause respiratory problems if inhaled, more than other types of smoke.

What Should You Do During a Wildfire?

Wildfire Safety Protocols

In Canada, wildfires or forest fires happen during the fire season, which is usually May through September. It is important that you know the signs, safety precautions, and emergency management for this year’s fire season. Be always prepared and follow these simple wildfire smoke guidelines:

1. Prepare a Wildfire Evacuation Plan – Have a plan in place before fires start. Know the best route away from the fire, where you’ll evacuate to, and how much money you might need to prepare.

2. Keep Yourself Updated – Listen to the news, local radio, or follow trusted social media sources for disaster updates. You can also download digital solutions that provide real-time information.

3. Have a Grab-and-Go Bag or Emergency Kit – Prepare an emergency kit with at least 72 hours worth of food and water that’s ready to grab and go. Remember the 5 Ps: People, Prescriptions, Papers, Personal Needs, and Priceless Items.

4. Properly Evacuate Your Area – Unplug and turn off any active appliances if able and remove flammable materials that could worsen the fire. Make sure to assist animals, individuals with disabilities, and the elderly in evacuating safely.

5. Stay Hydrated – Be sure to drink plenty of water while evacuating. Studies show firefighters can lose 6.7 to 9.5 liters of water per day during wildfire suppression.

Keeping your fire alarms, smoke detectors, and temperature sensors up to date is essential for staying prepared in case of unexpected fires.

Effects on the Environment, Businesses, and Health

When looking at the bigger picture, wildfires and their smoke can cause major damage to the environment. It may not be instant, but in the long-term, it will ruin air quality and damage the ozone layer. Wildfire smoke releases carbon dioxide (CO2) and other greenhouse gases into the atmosphere, further increasing global warming.

The fires also destroy wildlife habitats, food sources, and crops. Trees act like carbon sponges, absorbing CO₂ from the atmosphere and storing it. When they burn, that stored carbon is released back into the air, adding to climate change. Additionally, these burned forests can take decades to recover, which means a significant loss of natural resources for the people who depend on them.

You also have to think about the cost of the damage it will cause. The amount of homes, communities, and businesses that will be lost due to the fires. Businesses may shut down and evacuate, leaving everything behind. The smoke can travel thousands of miles and blanket cities causing closures, agricultural losses, bad working environments, thus also impacting tourism and productivity.

It can also affect your health if you don’t follow fire safety protocols. Inhaling the air pollutants will cause persistent coughing, wheezing, even leading to things as serious as heart disease. Face masks would be needed to protect yourself and others from the PM2.5 particles. Air purifiers, air quality monitoring tools, and Heating, Ventilation, and Air Conditioning (HVAC) systems would need to be installed in every building to help improve indoor air quality.