[AIVC, Air infiltration and ventilation glossary, 1992]:that portion of supply air that is outdoor air plus any recirculated air that has been treated for the purpose of maintaining acceptable indoor air quality.[ASHRAE Standard 62.1]:that portion of supply air that is outdoor air plus any recirculated air that has been treated for the purpose of maintaining acceptable indoor air quality.[ASHRAE Standard 62.2]:outdoor air delivered to a space that is intended to dilute airborne contaminants.