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What is Ozone?

Ozone is a highly reactive gas consisting of three oxygen atoms (O3). It is created when volatile organic compounds (VOC's) and nitrogen oxides (NOx) react with sunlight. At ground level, ozone is the main ingredient in smog, a health-threatening air pollutant. For additional information on ozone, please visit A Quick Ozone Lesson.

The Origin of Ozone Ingredients

The chemical components of ozone come from a variety of sources, many of which are man-made. By reducing the amounts of these chemicals that are released, we can reduce the formation of ground-level ozone.

The man-made sources of Volatile Organic Compounds (VOC's) include fossil fuel emissions released by industrial plants, gasoline engines (from large trucks to lawnmowers), manufacturing processes (like printing operations and painting), and numerous smaller sources (such as cleaning solutions).

The biogenic sources of Volatile Organic Compounds are essentially vegetation. Plants naturally release VOC’s, but the release can be triggered by activities like lawn mowing (the fresh "cut grass" smell is generated from VOC’s).

The second component of ozone is nitrogen oxides ( NOx). These emissions are a product of processes employing high temperature combustion. Power plants, industrial boilers, and motor vehicles are the principle NOx sources.

Source: US EPA -


The West Michigan Clean Air Coalition is a partnership of businesses, academic institutions, government agencies, industry, and non-profit organizations in Kent, Ottawa, Muskegon, and Kalamazoo counties working together to achieve cleaner air in the region through the education and promotion of voluntary emission reduction activities.

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