Dr Josef Allen, assistant professor of Harvard’s T.H. Chan School of Public Health, discussed Harvard’s Healthy Buildings Programme during the recent Global Wellness Summit in Mexico City, focusing on a new vocabulary to describe indicators of healthy environments.

Allen highlighted the link between material selection for buildings and the impact on human health. Humans spend 90 per cent of their time indoors, said Allen, and these interior environments are the areas most people are ignoring when it comes to improving workplace wellness for employees.

“We all know that going outside is healthier than being indoors, but many of us don’t know that even our carpets and chairs exude chemicals that affect our health, such as obesogens,” said Allen.

The average room gets one air change per hour, according to Allen, but in the 1980s this was reduced when air conditioning energy costs were reduced making the system more readily available – dropping down to 0.2 air changes per hour. In 1985, this stale air led to the Sick Building Syndrome, the name given to the concentration of indoor pollutants.

“It is no longer acceptable to be in a building that makes us ‘not sick,’” said Allen. “We need buildings that make us healthy.”

Allen conducted a review earlier this year on the effect green buildings and their indoor environment quality have on human health – specifically cognitive function.

To eradicate subjective results, he measured the cognitive function of 24 workers in optimised green buildings versus standard spaces. The working participants were taken into simulated environment and, from below, Allen controlled a number of variables, modifying one at a time each day. At the end of the day he administered a cognitive function test to the test subjects.

The three variables tested included the amount of outdoor air ventilation pumped indoors, the level of carbon dioxide, and the number of volatile toxic compounds in the atmosphere, which includes common chemicals found in personal care products, carpets and furniture.

The results showed a doubling of cognitive function scores for people experiencing increased outdoor ventilation.

“For decades we thought carbon dioxide percentages of these normal levels (1,400 parts per million) didn’t have a huge negative impact, but they do,” said Allen.

“Normal business key performance indicators (KPIs) of every company need to become health performance indicators (HPIs), as these are the metrics that matter the most.”

HPIs that employers should consider carefully – to improve the health and thus the productivity of employees – include the work space’s biophilic design, green building credits, access to green space, green cleaning procedures, wellness programmes, integrated pest management, ventilation and material selection, said Allen.

“By implementing and tracking these HPIs within the workplace, we will no longer be ignoring the space in which humans spend 90 per cent of their time,” he said.