Lower energy cost and less sick leave with displacement ventilation versus mixing ventilation

Experiences from cleanroom installations has frequently shown that displacement ventilation has a much higher efficiency than mixing ventilation with respect to particle and CO2 reduction, cooling efficiency etc. Another cleanroom experience is that low particle concentration benefits asthma and allergy sufferer. Low particle concentrations reduces the impact of other pollutants and enhance the quality of life for everybody. In an office, the level of discomfort this means less tiredness, better concentration and lower absenteeism. Risk of indoor airborne infection transmission increase with
decreasing ventilation efficiency. The investment cost for the cooling equipment and the cost for operating the cooling equipment is lower if the ventilation efficiency is high. All these factors should conclude that a good indoor environment is a sound investment. How much more efficient is the displacement ventilation in a normal office environment? We made a case study where we compared vertically displacement ventilation versus state of the art mixed ventilation in an office
environment.