Wildfire Smoke Information

During fire season, the air we breathe can become impacted by wildfire smoke.  Fine particles (particulate matter or PM) in smoke can cause health problems, especially for children, older people and those with respiratory conditions.

When your area is being impacted by wildfire smoke, please consider taking these precautionary measures: 

  • Healthy people should delay strenuous exercise.

  • Children and elderly people should consider avoiding outdoor activities, particularly prolonged outdoor exertion.

  • People with health-related illnesses, particularly respiratory problems, should remain indoors.

  • Keep windows and doors closed as much as possible, check to make sure they tightly seal. Use the recycle or re-circulate mode on the air conditioner in your home or car. Ensure that you are changing the filters in your HVAC according to manufacturers specifications; filters used during smoke events will have to be changed sooner.

  • If you'd like to improve the air inside your home, you can also obtain and run a portable indoor air purifier.  Studies have found air purifiers can reduce fine particulate matter by up to 90% indoors. The optimal air purifier contains a HEPA filter and does not generate ozone. Find a list of safe options.

  • If you want a higher level of protection, consider a mask that is N-95 or higher rated and fits well.  N-95 rated masks are designed to filter 95% of airborne particles.   

  • Keep airways moist by drinking lots of water. Breathing through a warm, wet washcloth can also help relieve dryness, however, the CA Department of Public Health recommends these masks.

  • The same particles in smoke that cause problems for people may cause some problems for animals. It is recommended that you limit the outdoor physical activity of your pets and working livestock, such as horses, in smoky conditions.

  • Wildlife may be confused or startled by smoky conditions. Please be cautious, as some animals may be moving about at unusual times of the day.

Exposure to smoke can cause coughing, watery and itchy eyes, difficulty breathing, and other problems. Persons experiencing questionable or severe symptoms from smoke exposure should seek professional medical advice and treatment. For more information about Smoke and Your Health, please refer to link #3 in the Wildfire, Smoke and Heath Effects section below. You can assess air quality based on visibility by following the step listed on the Wildfire Smoke Visibility Index site linked below (Link #2 under Wildfire, Smoke, and Health Effects).  

Wood smoke particulate matter (PM) is composed of wood tars, gases, soot, and ashes.  PM is a mixture of both solid particles and liquid droplets suspended in air. Small particulate matter with diameters of less than or equal to 10 microns (PM10) can be inhaled into the deepest recesses of the lungs where they stay for long periods of time.  In wildfire smoke, most particles are less than one micrometer, so the values obtained by measuring either PM10 or PM 2.5 are virtually interchangeable.  

Diameter Comparison: Human Hair, Sand, PM10, and PM2.5

 PM Diameter Comparison

During wildfires in El Dorado County, the AQMD works with the California Air Resources Board to install temporary monitors around the perimeter of the fire.  You can view the Current Air Quality Index (AQI) and Forecast at the link below (Air Monitoring Current Conditions) (Link # 1under Current Wildfire Information).

The California Air Resources Board maintains a monitor in South Lake Tahoe that monitors PM 10.  You can see the PM 10 levels from that monitor at the Air Quality and Meteorological Information (AQMIS) site linked below (Link #9 under Current Wildfire Information).

Data from the AQMIS and AirNow sites can be used to determine Air Quality Index with the AQI Calculator linked below. (Link #10 under Current Wildfire Information). 


Wildfire Information

Wildfire, Smoke, and Health Effects 

  1.  Fire Season: What to do Before a Wildfire

  2. Wildfire Smoke Visibility Index(PDF, 29KB)  to gauge the amount of smoke in their area and take precautions when the air quality worsens.  

  3. Research on DIY Air Cleaners to Reduce Wildfire Smoke Indoors | US EPA

  4. Recommended Children's Activity Levels during Wildfire Smoke Event - NIAA(PDF, 120KB)  

  5. When Wildfires Occur, Know How to Protect Yourself from Smoke(PDF, 25KB)

  6. Wildfire Smoke - A Guide for Public Health Officials (OEHHA)

  7. Air Resources Board Wildfire Smoke Health Impacts Video

  8. Sacramento Regional Air Quality Map and Index (Set the Pollutant parameter to Particulate Matter (PM) and Click on "Go". Click on “Animate” to view earlier AQI conditions for today.)  

  9. California Wildfire Disaster Guidance and Links 

  10. Safe Cleanup of Ash

  11. Interim Fact Sheet NIOSH Warns of Hazards During Cleanup Work Following Forest Fires(PDF, 34KB)

  12. Breathe Easy with an N95 Particulate Respirator During Smokey Days

  13. Wildfire Smoke Fact Sheet

  14.  Protect Your Lungs from Wildfire Smoke

  15. Reduce Exposure to Wildfire Smoke


Thank you for working with us to improve air quality