Fugitive Emissions from Refinery Process Drains, Volume I, Fugitive Emission Factors for Refinery Process Drains Emissions from refinery process drains are under increasing scrutiny, particularly with regard to volatile organic compounds (V OCs) and hazardous air pollutants because of the Clean Air Act Amendments of 1990. This publication is volume one of a three - part study initiated by API to update the AP - 42 emission factor for refinery process drains, which may overestimate refinery process drain fu gitive emissions. This vo lume contains simplified emission factors that can be used to quickly estimate total VOC emissions from refinery process drains. Se e also Publ 4639, Publ 4678, and Publ 4681