A Co-control benefit is the additional benefit derived from an Environmental policy that is designed to control one type of pollution, while reducing the Emissions of other pollutants as well. For example, a policy to reduce carbon dioxide emissions might reduce the combustion of coal, but when coal combustion is reduced, so too are the emissions of particulates and sulfur dioxide. The benefits associated with reductions in emissions of particulates and sulfur dioxide are the Co-control benefits of reductions in carbon dioxide.