Amy Cilimburg, Sarah Coefield, and Kerri Mueller

After a lovely, slow start to summer, it’s suddenly taking a turn— extreme heat advisories are in effect this week and some even had their first smell of wildfire smoke last weekend. As temperatures rise and fire danger increases, so too does the likelihood of smoke filling our valleys. That means it’s time to get smoke ready!

While wildfire smoke and heat often go hand in hand, this week, it’s just hot. Given the current heat advisory, please do what you can to stay healthy during these coming hot days: stay hydrated, adjust your activity levels, cool your home at night as best you can, and check in on your friends and neighbors. Heat can be deadly, and we need to work together to keep everyone safe.

Now on to fires and smoke—welcome to our fourth annual Wildfire Smoke Ready Week July 8-13. Every year, we dedicate a week to promoting preparedness in the face of increasing wildfire smoke. Human caused climate change is bringing longer and more intense fire seasons, yet there are ways we can prepare and stay healthy. In addition to being on the airwaves and on social media (#wildfiresmokeready), you can find us on:

-          July 10 at Out to lunch at Caras Park

-          July 12 at the Missoula Public Library (2-4 pm)

-          July 13 at both Farmers Markets

Why do we care so much about smoke? For those of us who’ve lived through past fire seasons, we know what it’s like. The air physically feels different. The smoky air is laden with fine particulate matter and volatile organic chemicals.

These components can cause a multitude of health effects, ranging from less severe (irritated eyes and nose, headaches, coughing) to more severe (reduced lung function, worsened asthma attacks and COPD symptoms, increased likelihood of heart attack and stroke, increased susceptibility to infectious disease, and increased hospitalizations and deaths.)

The most harmful ingredient in smoke is fine particulate matter 2.5 microns in diameter and smaller, known as PM2.5. These tiny particles can travel deep into your respiratory tract and even pass into the bloodstream, initiating a systemic inflammatory response. Not good!

While smoke is bad for everyone, children, teenagers, older adults, pregnant people, people with heart and lung disease, and people who can’t avoid exposures, such as outdoor workers and people living outside, are at greater risk of health impacts. That’s a lot of people.

For those who can go indoors when smoke rolls in, that’s a great first step to protect your health. Unfortunately, smoke still makes its way inside our homes and businesses. It enters via doors, windows, cracks, vents, and commercial HVAC systems. The longer a smoke event drags on, the more likely smoke will move indoors.

The good news is the fine particles in smoke can be readily filtered from indoor air!

Here’s how we can all take measures to protect ours and our loved one’s health when smoke rolls in (all this and more is updated regularly on

  1. Stay alert for changing conditions. Check local air quality monitors online at and check often! Look outside; if you can’t see five miles, the air quality is unhealthy.
  2. Reduce outdoor activity levels. The more physically active you are, the more air you breathe in, and the more smoke you’ll breathe into your lungs. Slow your roll a bit to cut some of your exposure and be creative with ways to stay active inside clean indoor spaces.
  3. Clean your indoor air! There are several ways to clean your air and they all come down to filtration. Also, be sure to keep your indoors cool. Heat is immediately dangerous. If you don’t have air conditioning, that may mean opening your windows at night and letting smoky air inside. Once your home has cooled, close doors and windows and filter the indoor air.
  4. Use HEPA portable air cleaners (PACs). Have at least one PAC and keep it in the room where you spend the most time. Make sure the PAC is sized appropriately for the room it’s in and does not generate ozone. If it’s in a large room, you’ll need a pretty beefy PAC or more than one. Close doors and windows to that room and run the PAC on the highest setting you find tolerable. Be sure to replace the filter when it gets dirty. You may need to change the filter more often than recommended during a smoke event.
  5. Make your own air cleaner with a box fan and furnace filters. Got a newer box fan lying around and some duct tape? Use it to clean your indoor air! Get a high efficiency HVAC filter (ideally MERV 13). Attach the filter on the back of the box fan, and you’re set. A basic DIY fan/filter is good for a room that’s about 150 ft2. Check our website for more tips on how to build your own air cleaner. Only use fans manufactured since 2012 (newer models have important safety features) and note these devices are noisier than HEPA PACs.
  6. For whole house filtration, upgrade the HVAC filter in your central air handler. Select the highest efficiency filter your home HVAC system can handle (ideally MERV 13, but MERV 11/12 will still help). Keep the fan running for continuous cleaning. Note that some central air systems may not be able to use high efficiency filters. If this is the case, use HEPA PACs or DIY fan/filters to clean your indoor air.
  7. For commercial HVAC systems, it isn’t as simple as upgrading the filter (although that’s an important first step!). Commercial HVAC systems have a lot of moving parts and functions that can let smoke indoors. Operators should follow ASHRAE’s “Planning Framework for Protecting Commercial Building Occupants During Smoke Events” found on our website here.
  8. Consider using an N95 or KN95 respirator mask. Note that these are hard to size for children, and facial hair can prevent a good seal. Do not use a respirator if you have trouble breathing through it.
  9. What about Pets? They too, are impacted by smoke pollution. Bring them inside and curtail their exercise when air quality is poor.
  10. Be fire safe! Do your part to avoid human-caused fires. Make sure campfires are cool to the touch before leaving them, make sure you aren’t dragging chains on the road, and don’t flick cigarette butts into dry grass. Find more information at!
  11. Take care of your mental health. Smoke can be gloomy and overwhelming. Please reach out to someone close to you or a mental health professional to share your feelings and for help.
  12. Take climate action. We know that the antidote to climate fear and frustration is to find ways to get involved: No one can do everything, but everyone can do something as we, collectively, make the energy transition, electrify our homes, shift our transportation system, add our voices for smart policies and new opportunities, and so much more. Check out Climate Smart Missoula’s Get Involved webpage.

Above all, don’t despair. Yes, fire season is on its way and smoke is an unfortunate part of most summers, but snow will fly and skies will clear. In the meantime, we know how to keep ourselves, our loved ones, and our communities healthy. And we can take action to stay healthy and do our part to reduce fossil fuel pollution!

Breathe safe!

Amy Cilimburg is the executive director at Climate Smart Missoula. Sarah Coefield and Kerri Mueller are Air Quality Specialists with Missoula Public Health. 

This Climate Connections column is brought to you by Climate Smart Missoula two Fridays of every month. Learn more about our work, support our efforts, and sign up for our e-newsletter at