Keep it Clean. Make Truckee Meadows a nOzone. Take Care of Our Air.

What is Ozone?

Ozone is a summertime pollutant of concern in the Truckee Meadows. Ozone is a gas that is found in two regions of the Earth’s atmosphere – at ground level and in the upper regions of the atmosphere. Ozone protects us from the sun’s harmful rays in the upper atmosphere, while ground-level “bad” ozone is harmful to our health and is the main component of smog. Ground-level ozone is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight.

Sunlight + Nitrogen Oxides (NOX) + Volatile Organic Compounds (VOCs) = Ozone

Sources of Ozone.

Emissions from industrial facilities and electric utilities, motor vehicle exhaust, gasoline vapors, and chemical solvents are some of the major sources of NOx and VOC.

Sources of NOx - 56% Motor Vehicles, 22% Utilities, 17% Industrial/Commercial/Residential Fuel Combustion, 5% All Other Sources. Sources of VOC - 50% Industrial/Commercial Processes, 45% Motor Vehicles, 5% Consumer Solvents.

What are the Health Effects of Ozone?

Ozone in the air we breathe can harm our health - typically on hot, sunny days when ozone can reach unhealthy levels. Even relatively low levels of ozone can cause health effects. People with lung disease, children, older adults, and people who are active outdoors may be particularly sensitive to ozone.

Children are at greatest risk from exposure to ozone because their lungs are still developing and they are more likely to be active outdoors when ozone levels are high, which increases their exposure. Children are also more likely than adults to have asthma.

Breathing ozone can trigger a variety of health problems including chest pain, coughing, throat irritation, and congestion. It can worsen bronchitis, emphysema, and asthma. Ground level ozone also can reduce lung function and inflame the linings of the lungs. Repeated exposure may permanently scar lung tissue.

EPA Ozone Health Statements

EPA Ozone Health Statements
Air Quality IndexHealth Statement
Good (0 - 50) None.
Moderate (51 - 100) Unusually sensitive people should consider limiting prolonged outdoor exertion.
Unhealthy for Sensitive Groups (101 - 150) The following groups should limit prolonged outdoor exertion:
  • People with lung disease, such as asthma.
  • Children and older adults.
  • People who are active outdoors.
Unhealthy (151 - 200) The following groups should avoid prolonged outdoor exertion:
  • People with lung disease, such as asthma.
  • Children and older adults.
  • People who are active outdoors.
Everyone else should limit prolonged outdoor exertion.
Very Unhealthy (201 - 300) The following groups should avoid all outdoor exertion:
  • People with lung disease, such as asthma.
  • Children and older adults.
  • People who are active outdoors.
Everyone else should limit outdoor exertion.
Hazardous (301 - 500) Everyone should avoid all outdoor exertion.

What is Northern Nevada Public Health Doing?

The annual smog check program is one of the measures in Washoe County to reduce emissions from motor vehicles. The Air Quality Management Division (AQMD) also permits sources of VOCs and NOx from business and industrial facilities. The AQMD also encourages using electric vehicles and equipment to reduce harmful emissions as well as alternative modes of transportation.

RTC Smart TripsThe Regional Transportation Commission of Washoe County has developed a Smart Trips program to assist local businesses to encourage their employees to use alternative modes of transportation, such as public transit, biking, carpooling and walking.

What You Can Do to Reduce Ozone

  • Conserve energy.
  • Carpool or use public transportation.
  • When air quality is healthy, bike or walk instead of drive.
  • Combine errands to reduce vehicle trips.
  • Limit engine idling.
  • When refueling, stop when the pump shuts off. Avoid spilling fuel and always tighten your gas cap securely.
  • Refuel vehicles after dusk, when emissions are less likely to produce ozone.
  • Keep your vehicle engines tuned up and tires inflated.
  • Use environmentally safe paints and cleaning products.
  • Use and properly seal cleaners, paints and other chemicals so smog-forming chemicals can’t evaporate.
  • Delay using gasoline-powered lawn and garden equipment or chemicals when air quality is unhealthy.
  • Be a Smog Spotter.

Smog Spotter Banner

Health Tips

  • Make it a habit to know what the Air Quality Index (AQI) before planning your activities.
  • Reduce the time you are active outdoors when ozone levels are elevated.
  • Schedule outdoor activities for the morning or evening when ozone levels are usually lower.
  • When ozone levels are high, choose a less intense activity.

Last modified on 08/15/2023