Some Buildings Promote Better Productivity than Others

Improved indoor environmental quality doubled participants’ scores on cognitive function tests, according to a study by researchers at the Harvard University T.H. Chan School of Public Health’s Center for Health and the Global Environment, SUNY Upstate Medical University and Syracuse University.

Employees’ cognitive performance scores averaged 101% higher in green building environments with enhanced ventilation compared to a conventional building environment. “We know green buildings conserve natural resources, minimize environmental impacts and improve the indoor environment, but these results show they can also become important human resource tools for all indoor environments where cognitive abilities are critical to productivity, learning and safety,” says John Mandyck, chief sustainability officer for United Technologies, the primary supporter of the study.

The double-blind study evaluated the cognitive performance of 24 participants who performed normal work activity in a laboratory setting that simulates conditions found in conventional and green buildings, as well as green buildings with enhanced ventilation. At the end of each day, participants completed a 1.5-hour cognitive assessment. Researchers measured cognitive function for nine functional domains, including basic, applied and focused activity levels; task orientation; crisis response; information seeking; information usage; breadth of approach; and strategy.

The largest improvements in cognitive function test scores occurred in the areas of crisis response, information usage and strategy. Crisis response scores were 97% higher for employees in the green environment and 131% higher for the green environment with enhanced ventilation and lower carbon dioxide levels compared to the conventional environment. Information usage scores for green and enhanced green environments were 172% and 299% higher than in the conventional environment, respectively. For strategy, green and enhanced green scores were 183% and 288% higher than the conventional environment.

“This study suggests that indoor environments can have a profound impact on the decision-making performance of workers, which is a primary indicator of worker productivity,” says Dr. Joseph Allen, Assistant Professor of Exposure Assessment Science at the Harvard T.H. Chan School of Public Health, Director of the Healthy Buildings Program at the Center for Health and the Global Environment at Harvard Chan School, and Principal Investigator for the study.

The full report is available at and