Today an acceptable indoor air quality is mainly defined by specifying the required level of ventilation in air changes per hour or the outside air supply rate. The increasing societal need for energy efficiency will often result in very tight buildings. This means that the amount of outside air supplied by infiltration is not enough to provide the required ventilation. In some standards, the required ventilation is based on adapted people (occupants) while other standards refer to un-adapted persons, who have just entered a room. Which approach is correct? Or should it depend on the type of space or occupancy? The present talk provides an overview and discusses the criteria used for specifying required ventilation rates and suggests ways of meeting the criteria in a more energy-efficient way by means of improved ventilation effectiveness, use of air cleaning, and by means of demand-controlled ventilation.

About the speaker

Bjarne W. Olesen holds a Master's degree in civil engineering, 1972, and a Ph.D. from the Laboratory of Heating and Air Conditioning, Technical University of Denmark, 1975. Since January 2004 he became a full-time professor at the International Centre for Indoor Environment and Energy, Technical University of Denmark. He was awarded the Ralph Nevins Award (1982), Distinguish Service Award (1997), Fellow Award (2001) and Exceptional Service Award (2006) from ASHRAE, the Medal of Honour from the German Engineering Society (VDI-TGA, 2005), International Honorary Member of SHASE (Society of Heating, Air-Conditioning, and Sanitary Engineers of Japan) and Honorary member of AICARR (Italian Society for HVAC). He served as the ASHRAE president during 2017-18. He is active in several ASHRAE-CEN-ISO standard committees regarding indoor environment and energy performance of buildings and HVAC systems. Has published more than 450 papers including more than 90 in peer-reviewed journals.