A team led by HNEI was published in the October 2020 volume of the journal Developments in the Built Environment, on the significance of user awareness and training when operating a mixed-mode building that is designed for both natural ventilation and mechanical cooling. When comparing CO2 levels in two identical free standing classrooms, HNEI Associate Specialist Jim Maskrey, consultant Sara Cerri, and Eileen Peppard of the UH Sea Grant College Program, found differences of up to a factor of three in the two buildings operated by different faculty and users. Lethargy, headaches, and restlessness and the resulting diminished learning environment are among the many health effects that are caused by low CO2. Natural ventilation provided by opened windows circulates enough outside fresh air to maintain a healthy CO2 level. When the doors and windows remain closed, there is insufficient outside air, causing an elevation in CO2, frequently higher than ASHRAE recommended levels. The difference between those two conditions lies in the instructor’s training and awareness, which in turn leads to the operational choice to utilize natural ventilation features.
This work is summarized in the open access paper “Retaining a Healthy Indoor Environment in On-Demand Mixed-Mode Classrooms” available at https://dx.doi.org/10.1016/j.dibe.2020.100031.