The Nevada County Public Health Officer and the Northern Sierra Air Quality Management District are issuing a joint air quality health advisory to notify the public of potentially poor air quality conditions through July 24th caused primarily by the Detwiler Fire burning in Mariposa County.

Numerous factors influence fire and smoke behavior, making it difficult to predict exactly when or where smoke will be at ground level.  Eastern Nevada County, including Truckee, is likely to see the highest levels of smoke through the weekend.  With clear skies and high afternoon temperatures, we may also see elevated ozone concentrations in western Nevada County, especially in the evenings and overnight.

Concentrations of fine smoke particles (PM2.5) and ozone are expected to at least reach the “Unhealthy for Sensitive Groups” range periodically over the advisory period.   Sensitive Groups include elderly individuals, children, people with asthma, people with heart or lung conditions, pregnant women and anyone who is exercising or working hard outdoors.  Exposure to elevated ozone and PM2.5 concentrations can result in eye and throat irritation, headaches, nausea, shortness of breath, congestion, coughing, impaired lung function and chest pain.  Because of this, individuals should be aware that it is possible for smoke to affect both indoor and outdoor activities.

If you can see smoke around you or smell smoke, it is advisable to avoid unnecessary outdoor activities, especially if you are in an area where visibility is noticeably reduced.  Sensitive individuals in particular should avoid prolonged or heavy outdoor exertion, especially during the late afternoon and evening.

Here are additional ways to reduce your smoke and ozone exposure:

  • Stay indoors with the windows and doors closed; if possible, run the air conditioner on the “recirculate” setting.
  • Leave the smoke-impacted areas until conditions improve, if possible.  For those without air conditioning, keeping windows and doors closed on hot days can result in very high indoor temperatures so consider staying with friends, family, or alternate locations.
  • Reduce unnecessary driving. If traveling through smoke-impacted areas, be sure that your vehicle’s ventilation system is on recirculate.
  • Keep airways moist and stay hydrated by drinking plenty of water.
  • Avoid cigarette smoke.

Anyone experiencing questionable or severe symptoms such as chest pain, chest tightness, shortness of breath, or severe fatigue is advised to contact their doctor.  This is important for not only people with chronic lung or heart disease, but also for individuals who have not been previously diagnosed with such illnesses. Smoke can “unmask” or produce symptoms of such diseases. Also, when feasible, pets should be brought indoors when outdoor air quality is poor.

Keep in mind that air quality can change rapidly at different times during the day due to wind shifts; therefore, it is important to monitor the smoke throughout the day in your area and make outdoor plans accordingly.

Information on air quality and smoke can be found at (PM and Ozone hourly information) (smoke information based on fire incidents) (PM and ozone combined) (air quality guide for particle pollution)  (ozone)