Definitions for "RACT"
Reasonably Available Control Technology is the technology required for existing major source in nonattainment areas. RACT typically reflects controls the EPA has identified in Control Technique Guidelines (CTG) or other guidance. SIPs must be revised to required RACT for control of VOC emissions from sources for which EPA has published (or will publish) a CTG.
Reasonable Available Control Technology
Reasonably available control technology. Control technology that is both technologically and economically feasible. The term usually applies to existing sources in nonattainment areas.