General opinion on ventilation is that the air inside a home is “dirty” and needs to be diluted with fresh air from outside in order to keep it clean. This article investigates this theory, with particular attention to homes in hot and humid climates, where the air outside might not seem so fresh in the middle of the summer. The general ventilation standard in the United States is that every occupant of a building requires 7.5 cubic feet per minutes (CFM) of fresh air and an additional 1 CFM per 100 square feet of the building. This suggests that diluting dirty air with clean air might not be the best method to improve air quality.
Read the full article here: Indoor-Air Quality and Ventilation for Homes in Hot-Humid Climates