Indoor Environment Program - 1996 Annual Report

The forty-five chemists, physicists, biologists, architects, engineers, staff, and students of the Indoor Environment Program are all working to solve the problems of indoor air quality, health, comfort, and energy use associated with the indoor environment. A common thread throughout this work is the importance of ventilation--both for its role in supporting human health and comfort as well as for its liability in requiring large amounts of energy to heat and cool it. The importance of understanding these interactions can be illustrated by two examples: the health and productivity of workers (Fisk and Rosenfeld, 1996) and the performance of sensitive equipment in clean room environments (Faulkner, et d., 1996). During the past year, we estimated the magnitudes of health and productivity gains that may be obtained by providing better indoor environments. The ratio of the potential financial benefits of improving indoor environments to the costs of the improvements ranges between 20 and 50. A second example is from our Clean Room Energy Efficiency Study: Clean rooms utilize large amounts of electricity to operate fans that recirculate air at very high flow rates through particle filters. Usually, the fans operate continuously at full speed, even when the clean room is unused. To reduce the energy use in a research clean room, the rate of air recirculation was controlled in response to real-time measurements of particle concentration. With this new control system, fan energy use decreased by 65% to 85% while maintaining particle concentrations below the allowable limits except during occasional one-minute periods. The estimated payback period for this technology is one to four years