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Wildfire Smoke and Your Health: Health and Safety Information, Education, and Resources for the Community

  • July 31, 2026
  • By Zaw Wai Htoo

By: 

Passport Photo of Dr. Zaw Wai Htoo, Advisor, UCCE

Dr. Zaw Wai Htoo, Community Nutrition and Health Program
University of California Cooperative Extension – San Francisco North Bay

Posted: July 30, 2026

Wildfire smoke can affect communities many miles from an active fire. Even if you are not near the fire itself, smoke can travel long distances and reduce air quality, potentially affecting your health.

As the Woodside Fire continues in Sonoma County, smoke may affect air quality across parts of Sonoma County and neighboring communities, depending on weather conditions and wind patterns. Air quality can change rapidly throughout the day. We encourage everyone to stay informed and take practical steps to reduce smoke exposure.
 

Educational infographic developed by the Community Nutrition and Health Program, University of California Cooperative Extension, San Francisco North Bay, summarizing evidence-informed recommendations for reducing wildfire smoke exposure and protecting health. The infographic provides practical guidance that can be used during the current Woodside Fire and future wildfire smoke events.
Figure 1. Educational infographic summarizing key health information and practical recommendations to help individuals, families, and communities reduce exposure to wildfire smoke. Topics include understanding the Air Quality Index (AQI), strategies for improving indoor air quality, appropriate respirator use, protecting higher-risk populations, recognizing symptoms of smoke-related illness, and accessing official public health and emergency resources. Although developed in the context of the Woodside Fire, the recommendations are broadly applicable to wildfire smoke events.
Current Situation
 
Color-coded AirNow AQI map showing wildfire smoke impacts across Sonoma County and the North Bay. Several locations are in the Hazardous category (AQI 300+), with surrounding areas ranging from Good to Very Unhealthy air quality.
Figure 2. AirNow Air Quality Index (AQI) map showing regional air quality conditions across Sonoma County and neighboring North Bay counties at the time the screenshot was captured on July 30, 2026. Color-coded monitoring locations illustrate varying air quality levels, with dark brown indicating Hazardous air quality (AQI 300 or higher) associated with wildfire smoke. The map demonstrates that wildfire smoke can affect communities well beyond the immediate fire area. Air quality conditions may change rapidly as weather, wind, and wildfire activity evolve. Please refer to AirNow.gov for the latest air quality information. Source: AirNow https://www.airnow.gov/?
Understanding the Air Quality Index (AQI)

The Air Quality Index (AQI) is a tool developed by the U.S. Environmental Protection Agency to communicate how clean or polluted the air is and the potential health effects associated with current air quality conditions.

General guidance
  • AQI 0–50 (Good)- Air quality poses little or no health risk.
  • AQI 51–100 (Moderate)- Unusually sensitive individuals should consider reducing prolonged outdoor exertion.
  • AQI 101–150 (Unhealthy for Sensitive Groups)- Children, older adults, pregnant individuals, and people with heart or lung disease should reduce prolonged outdoor activities.
  • AQI 151–200 (Unhealthy)- Everyone should reduce prolonged or strenuous outdoor activities.
  • AQI 201–300 (Very Unhealthy)- Avoid outdoor activities whenever possible and stay in cleaner indoor air.
  • AQI 301 and above (Hazardous)- Avoid outdoor exposure, remain indoors if it is safe to do so, and follow guidance from public health and emergency officials.
Practical Steps to Reduce Smoke Exposure

You can help protect yourself and your family by taking the following actions-

  • Check current AQI conditions before spending time outdoors.
  • Reduce or postpone strenuous outdoor activities when smoke levels are elevated.
  • Keep windows and doors closed when outdoor air is smoky and indoor temperatures remain safe.
  • Create a cleaner indoor space by using a portable HEPA air cleaner if available.
  • If you do not have a portable air cleaner, a properly constructed DIY box fan with a MERV-13 filter may help improve indoor air quality when used according to safety guidance.
  • Avoid activities that create additional indoor air pollution, such as smoking, burning candles or incense, using fireplaces, or prolonged frying and broiling.
  • If outdoor exposure cannot be avoided, wear a well-fitting NIOSH-approved N95 respirator.
  • Stay hydrated and monitor yourself and family members for symptoms related to smoke exposure.
Protect Those at Greater Risk

Some individuals are more vulnerable to wildfire smoke and may experience health effects sooner than others.

These include-

  • Older adults
  • Infants and young children
  • Pregnant individuals
  • People with asthma, COPD, or other lung diseases
  • Individuals with heart disease
  • Outdoor workers
  • People with disabilities or chronic medical conditions
  • Individuals without access to cleaner indoor air or air filtration

Please consider checking on neighbors, family members, and friends who may need additional assistance during periods of poor air quality.

Know the Difference Between an Evacuation Warning and an Evacuation Order

During an active wildfire, emergency officials may issue evacuation notices (tap on this link to view).

  • Evacuation Warning- Be prepared to leave quickly if conditions worsen. Gather medications, important documents, pets, and essential supplies.
  • Evacuation Order- Leave immediately using designated evacuation routes. Do not delay to gather additional belongings.

Always follow instructions (tap on this link to view) from local emergency management officials.
 

CAL FIRE map showing the Woodside Fire location with surrounding evacuation zones. Red areas represent Evacuation Orders, and yellow areas represent Evacuation Warnings.
Figure 3. Screenshot of the CAL FIRE Woodside Fire incident map showing the fire location (approximately 143 acres, based on the latest official mapping) and current evacuation zones as of July 31, 2026. Red areas indicate Evacuation Orders, and Yellow areas indicate Evacuation Warnings. Conditions, fire size, and evacuation zones may change rapidly. Please refer to CAL FIRE and Sonoma County Emergency (SoCoEmergency) for the latest incident information and public safety updates. Basemap attribution: Esri, Vantor, Earthstar Geographics, and the GIS User Community | California State Parks, Esri, TomTom, Garmin, SafeGraph, GeoTechnologies, Inc., METI/NASA, USGS, Bureau of Land Management, EPA, NPS, USDA, and USFWS. Source: CAL FIRE – Woodside Fire Incident (https://www.fire.ca.gov/incidents/2026/7/30/woodside-fire/#newsUpdates).
Zoomed-in CAL FIRE incident map showing the Woodside Fire perimeter and nearby evacuation zones. Red areas indicate Evacuation Orders, while yellow areas indicate Evacuation Warnings. The map highlights the areas directly affected by the incident.
Figure 4. Zoomed-in screenshot of the CAL FIRE Woodside Fire incident map showing the fire location, incident perimeter, and nearby evacuation zones as of July 31, 2026. Red areas indicate Evacuation Orders, and yellow areas indicate Evacuation Warnings. This closer view provides additional geographic detail of the areas affected by the incident. Conditions, fire size, and evacuation zones may change rapidly. Please refer to CAL FIRE and Sonoma County Emergency (SoCoEmergency) for the latest incident information and public safety updates. Basemap attribution: Esri, Vantor, Earthstar Geographics, and the GIS User Community, California State Parks, Esri, TomTom, Garmin, SafeGraph, GeoTechnologies, Inc., METI/NASA, USGS, Bureau of Land Management, EPA, NPS, USDA, and USFWS. Source: CAL FIRE – Woodside Fire Incident (https://www.fire.ca.gov/incidents/2026/7/30/woodside-fire/#newsUpdates).
Watch for Smoke-Related Symptoms

Wildfire smoke may cause-

  • Coughing or wheezing
  • Shortness of breath or difficulty breathing
  • Eye, nose, or throat irritation
  • Headache
  • Fatigue
  • Chest discomfort or chest pain
  • Rapid or irregular heartbeat

Seek medical attention promptly if symptoms become severe or do not improve. Call 911 immediately for severe difficulty breathing, chest pain, signs of a heart attack or stroke, loss of consciousness, or another medical emergency.

Stay Informed

For the latest wildfire and air quality information, please visit:

  • AirNow Fire and Smoke Map
  • CAL FIRE Incident Information
  • Sonoma County Emergency Information
  • California Department of Public Health
  • Centers for Disease Control and Prevention

The Community Nutrition and Health Program at the University of California Cooperative Extension, San Francisco North Bay, provides timely, evidence-informed educational resources that help individuals, families, and communities make informed decisions to protect their health during emergencies.

While wildfire smoke can pose significant health risks, practical actions such as monitoring air quality, reducing smoke exposure, creating cleaner indoor environments, and staying informed through trusted sources can help reduce those risks.

This educational resource is intended to support public health awareness and preparedness. It does not replace guidance from healthcare professionals, emergency management agencies, or local public health authorities. During an active wildfire, always follow official evacuation orders, emergency alerts, and public safety instructions.

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