Background
Ozone (O3) is a gas composed of three oxygen atoms. It is not usually emitted directly into the air. Generally ozone is created by a chemical reaction between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight.
Ozone is a strong irritant that adversely affects human health. Breathing air containing ozone can reduce lung function and increase respiratory symptoms, thereby aggravating asthma, bronchitis, or other respiratory conditions including chest pains and wheezing. Both short-term and long-term exposure to ozone can irritate and damage the human respiratory system, resulting in:
- increased susceptibility to respiratory infections;
- increased risk of cardiovascular problems such as heart attacks and strokes;
- increased doctors visits, hospitalizations, and emergency room visits;
- increased school absenteeism; and
- an increase in mortality/premature deaths, especially in people with heart and lung disease.
The adverse effects of ozone are not just limited to humans. Ozone can also cause damage to crops and natural vegetation by acting as a chemical oxidizing agent. Ground-level ozone is one of the air pollutants regulated by the federal and state government. Many parts of California, including Sacramento County, violate federal ozone health standards. Reducing ozone to levels below state and federal standards is one of the primary goals of the air districts.
The Sacramento region is designated a nonattainment area for the federal 8 hour standard ozone air quality standard. We are required to undertake planning efforts to reach this health-based standard. The region includes all of Sacramento and Yolo counties and portions of Placer, El Dorado, Solano, and Sutter counties.



