How Can I Stay Safe From Wildfire Smoke?

#EcoAdvice from our expert

Dear Dr. Donley,

As if being worried about an invisible pathogen isn’t enough, I now find myself surrounded by very visible smoke from wildfires that are covering the West. How do I make sure my family stays safe from the thick smoke that’s all around us, and how can I tell when it’s safe to go outside?


Just Looking for a Smoulder to Cry on

Dear Hanging by a Thread,

Sooooo…2020, right?

In my home state of Washington, I’ve also found myself homebound for multiple reasons, including the thick haze in the air that stings my eyes every time I go outside for more than five minutes. Wildfires up and down the West Coast are getting worse and burning longer, driven largely by decades of wildfire suppression and the climate crisis humans have created.

Do what you can to stay safe. That means checking the air quality in your area and staying indoors as much as possible when air-quality readings are high, and using indoor air filters when possible. The air quality index (AQI) is a simple indicator of the severity of major air pollutants that are regulated in the U.S. Wildfire smoke can contain a whole host of pollutants, the most concerning of which is thought to be fine particulate matter (PM2.5 and PM10) — both of which are accounted for in the AQI.

There are multiple places to get up-to-date info on AQI in your area, sometimes even neighborhood by neighborhood, from sites like AirNow, PurpleAir and IQAir. PurpleAir tends to be a bit more conservative in its AQI measures with wildfire smoke but are updated in real time, allowing you to get up-to-date information when conditions are rapidly changing. The U.S. government’s AirNow site is probably a bit more accurate but is only updated every couple of hours.

There are also many other great air-quality resources. I like to monitor trends from multiple sites to get information on air quality in my area. Keep in mind that the accuracy of the data will depend on how close you are to a monitoring station, which can range from a few feet to hundreds of miles.

AQI is divided into six color-coded categories to help people evaluate air-quality risks, ranging from 0 (low risk) to 300+ (high risk). If the AQI near you is lower than 100, the primary air pollutants fall below levels EPA deems acceptable for most people. That doesn’t necessarily mean it’s risk-free, as some air pollutants have no exposure levels that don’t pose some risk. Levels above 50 should really not be considered safe, but deciding on a level you feel comfortable with to go outside and engage in normal activity is entirely up to you.

One note on the AQI range of 101–150: The EPA says these levels can be unhealthy for people in “sensitive groups.” This terminology is misleading, as the agency’s definition of sensitive groups includes people with pre-existing conditions as well as the elderly, healthy children and healthy people who exercise or work outside. Not exactly the “sensitive groups” most people think of. Anything above 150 means you really need to stay inside.

Keep in mind that indoor air quality can also be very poor, depending on whether you have pets, how often you clean, if you cook with natural gas or propane rather than electric, the types of cleaning products you use, etc. So a “moderate” AQI outside might actually be better than what you’re breathing indoors, which is why it is important to use air filters if possible when you can’t open doors or windows to improve indoor air quality.

Unless the air quality outside is hazardous, you should always try to vent the air when you cook on the stove or oven and only use a vacuum with a HEPA filter. Though in vogue with home cooks, natural gas ranges release a lot of pollution in your house (and into you when you’re standing right over them). Best to go electric or induction whenever possible. Make sure to replace the filter in your HVAC system or air purifier every few months, and spring for a good one if you can — the cheap knock-off brands don’t have the same quality control that popular name brands do.

Air purifiers are great at increasing the air quality in your home, but some can be pretty pricey. There’s always the ol’ duct-tape-a-furnace-filter-to-a-box-fan-trick, which can be a great low-cost DIY air filter. Just make sure the filter has a MERV rating of 13 or higher. And don’t forget to drink water. Our bodies need a lot more of it when we’re breathing smoke.

In times like these, when just getting through the day can be a struggle, it’s easy to just focus on what you can do in the moment to weather the storm. But always remember how you’re feeling in this moment, particularly when you participate in the most important action you can take: voting. Retreating into your house and protecting yourself is something you should be doing now, but it won’t prevent this from happening year after year. Support candidates and ballot measures that embody your sense of urgency in fixing the climate crisis.

This will be the new normal if we don’t take action. So, please, take care of yourself right now in every way you need to — and then funnel all your anger, frustration and sadness into fighting for bold, meaningful action on global climate change.

Stay wild,

Dr. Donley

Dr. Nathan Donley is a scientist at the Center for Biological Diversity who answers questions about how environmental toxins affect people, wildlife and the environment. Send him your questions at

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Nathan Donley

Nathan Donley

Senior scientist at the Center for Biological Diversity, former cancer researcher at Oregon Health and Sciences University