Best available control technology (BACT) is a pollution control standard mandated by the United States Clean Air Act.The U.S. Environmental Protection Agency (EPA) determines what air pollution control technology will be used to control a specific pollutant to a specified limit. When a BACT is determined, factors such as energy consumption, total source emission, regional environmental impact, and economic costs are taken into account. It is the current EPA standard for all polluting sources that fall under the New Source Review guidelines and is determined on a case-by-case basis.The BACT standard is significantly more stringent than the Reasonably Available Control Technology standard but much less stringent than the lowest achievable control technology standard.