Concentration versus m3 air per hour:the battle of the assessors?

Abstract

The opposite of the performance approach is the prescriptive approach. If we refer to an amount of air changes per hour (ACH) or a flow rate in m3 air per hour (qv) we assume a certain performance of the ventilation as with these parameters we now prescribe the ventilation. But, with focus on the indoor environment, a certain ‘x’ m3 air per hour is not the targeted outcome of ventilation. What is desired of ventilation are performances such as health and (local) comfort; for example the sleep quality in a sleeping room. Instead of air change per hour we should be talking about air quality and thermal comfort or maybe even physiological indicators that directly relate to health and comfort