What we think we know about ventilation

How much do we really know about ventilation ?It is admitted that for a good indoor air quality in a building, the amount of outdoor air ventilation is one of the most important determinants , but many critical questions and misunderstandings exist :Do we know the quantity of outdoor air is even needed in buildings? And about the ventilation requirements : they treat all the huge variability in buildings the same. The results of ventilation rates often reveal significant gaps between design intent and actual performance.Too many questions remain about ventilation so the research has to carry on.