The evidence that ‘green’ offices have a significant positive impact on the health and productivity of workers continues to mount.

We know that workers take fewer sick days, experience better health and work more productively in a workspace where buildings are designed, run and maintained with health and well-being in mind. Now, we also know that brainpower is better, too. Studies have shown that cognitive functioning is significantly better for workers in ‘green’ offices.

So what makes an office ‘green’? Having a low environmental impact is perhaps the first and most obvious factor that comes to mind, but from a health perspective, a lot of it comes down to having plenty of ventilation and air flow, low levels of chemicals such as volatile organic compounds (VOCs), and the amount of carbon dioxide present in the air. Each of these can have their own effects on the Indoor Environmental Quality (IEQ) of a building and, in turn, on our health.

A 2016 study tested the cognitive function of workers in simulated office environments: a conventional office environment that mirrored typical ‘non-green’ buildings, a ‘green’ low-VOC environment, and a ‘green +’ environment with higher ventilation rates.

Perhaps not surprisingly, workers performed better in the ‘Green’ and ‘Green +’ offices compared to conventional workspaces. On average, cognitive scores were 61 per cent higher on the Green building day and 101 per cent higher on the two Green+ building days than on the conventional building day. Specifically, the working environment had the biggest impact on participants’ crisis response, strategy, and information usage abilities.

The study also examined the effects of carbon dioxide concentration on cognitive function. Carbon dioxide is often viewed as an indicator of ventilation (and therefore, the overall indoor air quality) in a space. However, some recent research has suggested it should be viewed as a direct pollutant in its own right. Researchers found significant declines in cognitive function when carbon dioxide concentrations reached levels common in indoor spaces (approximately 950 parts per million). A separate study also showed that increasing carbon dioxide concentrations affected purely physiological factors such as heart rate.

In terms of building design, getting the right balance between adequate ventilation and energy efficiency can be tricky. However, ensuring a steady supply of outside air will help lower the levels of pollutants inside. These can include a variety of airborne compounds such as particle matter, nitrogen dioxide, allergens, and VOCs, all of which can trigger a range of adverse symptoms in building occupants. In fact, the economic costs of workers suffering from ‘sick building syndrome’ are higher than the savings from improved energy efficiency of well-sealed buildings. Efforts have been made since the early 1990s to improve building design to improve energy efficiency and ventilation, and these are important factors for Green Star or LEED rated or WELL certified buildings.

It’s also important to control indoor sources that have an impact on indoor environmental quality. Simply adding some indoor plants to a space can help filter the air and reduce levels of indoor pollutants in a room. Choosing low-VOC or no-VOC paints and cleaning products, as well as furnishings and other fittings such as flooring materials, will also have a positive impact on indoor environmental quality. Opting for products and materials with third-party sustainability certification is an easy way to know that products have been independently assessed for their impact on health and the environment.