Wildfire Air Quality in the Pacific Northwest

Wildfire smoke has become a recurring reality across the Pacific Northwest, and the fine particles it carries make monitoring air quality essential for anyone in its path. Knowing how to read the Air Quality Index and how to keep that smoke out of your home lets you protect your family through fire season. Here is what to watch and what to do.

Understanding the Air Quality Index

The Air Quality Index (AQI) measures pollution in the air and translates it into a simple, health-based scale. It accounts for particulate matter (PM2.5 and PM10), ground-level ozone, carbon monoxide, sulfur dioxide, and nitrogen dioxide. During wildfires, PM2.5, the fine particles small enough to reach deep into your lungs, is the pollutant that matters most. The AQI sorts conditions into six categories running from "Good" (0-50) to "Hazardous" (301+), with color codes that make the day's risk easy to read at a glance.

For a fuller walkthrough of the scale and how to act on it, see our guide to harnessing the Air Quality Index to safeguard your indoor air.

Staying informed in the Pacific Northwest

As wildfires grow more frequent and intense in the region, staying current on the AQI is a daily habit worth building during fire season. Government resources like AirNow, along with local environmental agencies, mobile apps, and many smart home devices, provide real-time readings for your area. Checking before you plan outdoor activity, or before deciding whether to open windows, lets you get ahead of a smoky day rather than react to it.

Protecting your health when smoke rolls in

When the AQI climbs, a few steps sharply reduce your exposure:

• Stay indoors and seal up. Close windows and doors to keep outdoor smoke from getting in, and avoid activities that add indoor particulates, like frying food or burning candles.
• Limit outdoor exertion. Skip strenuous activity outside and minimize time outdoors during the smokiest hours.
• Wear a proper mask outside. A well-fitted N95 or N99 respirator filters the fine particles that cloth and surgical masks let through.
• Run a portable HEPA purifier. In the room where you spend the most time, a HEPA unit clears fine smoke particles the rest of the house can't keep up with.

Your HVAC filter is the first line of defense

Your central system can do a lot to keep indoor air breathable, but only with the right filter. To capture fine wildfire smoke, you need a high-efficiency filter, and MERV 13 is the sweet spot for smoke particles in homes whose systems can handle it. Set your thermostat fan to run continuously during smoke events so air keeps cycling through the filter, and change that filter more often, since heavy smoke loads it far faster than normal. Our guide to wildfire smoke and what MERV rating helps explains the trade-offs, and choosing the best AC filters for wildfire smoke helps you pick.

Because higher-MERV filters restrict airflow more, confirm your system can handle one before upgrading, and watch for reduced airflow. For a broader plan, see ensuring clean air during wildfire season and how to mitigate harmful airborne particles from wildfire smoke.

Stock up before fire season hits: browse our AC filters, furnace filters, and full range of HVAC filters, or order a custom size if your system takes an odd fit. Free shipping applies over $50.

Frequently asked questions

What MERV rating is best for wildfire smoke?

MERV 13 is the practical target for capturing fine smoke particles in a home, provided your system can handle the airflow. If it can't, use the highest MERV your unit supports and pair it with a portable HEPA purifier in key rooms.

Should I run my HVAC fan during a smoke event?

Yes. Setting the fan to run continuously keeps pulling air through your filter, which steadily removes smoke particles. Just be ready to change the filter more often, because smoke loads it quickly.

What AQI level is unhealthy?

AQI above 100 is unhealthy for sensitive groups, and above 150 is unhealthy for everyone. Once readings climb into those ranges, stay indoors, seal your home, run filtration, and limit outdoor exertion.