What Is Ozone?

Human Sources
vehicles
furnaces
oven burning
leaf burning
dusty coal piles
power plants
adhesives
petroleum storage
factories
landfills
commercial printers

dry-cleaning solvents
filling stations
charcoal grills
gas lawn mowers
off-road vehicles
jet skis, boats
airplanes
refrigerants
paint, solvents
fireplaces, woodstoves

Natural Sources
lightning
pine trees
brush and forest fires
cattle
volcanoes
geysers
wetlands/swamps