Indoor Air Quality and Brain Performance

by / Wednesday, 23 December 2015 / Published in Green Building Consulting, Healthy Building Inspections & Testing
IAQ and Brain performance

Indoor Air Quality and Brain Performance

The Harvard School of Public Health recently released results of a small study that supports what green building enthusiasts have known for years – Indoor Air Quality and Brain Performance are directly connected. While small (24 real people), the double-blind study appears to have been well-crafted and executed under exacting controls. With much ado, the researchers rolled out the results to an enthusiastic audience at GreenBuild 2015. While the results seem rather commonsense, I’m delighted to see Harvard and the National Institute of Health begin to pay more attention to IAQ and cognitive function.

Grim, but true, extrapolated across a larger population the meaning of this study may have dire consequences for the future of our civilization. While the EPA has been focusing most its regulatory efforts on outside air, and OSHA focuses only on the worst-of-the-worst offenders, the common worker and building occupant has largely been neglected – at least in terms of governmental attention and regulation to indoor air quality (IAQ). And where regulations do exist, such as minimum required ventilation rates, they are often not enforced or regulated closely enough to ensure widespread adoption.

Average IEQ Conditions for Mental Aptitude Study

Six Days of Cognitive Function Testing

Sound like fun? Only if you’re masochistic!

24 darling volunteers went through many different cognitive functioning tests over the course of 6 days. The only significant variables that changed were concentrations of CO2, Volatile Organic Compounds (VOCs), and Aldehydes. The chart above shows some of the primary variations tested that were meant to reflect a “green or conventional buildings.”

IAQ Cognitive Domains Tested

Cognitive Function in Plain English

Cognitive what?!?!  The above chart illustrates nine different areas of brain function that were specifically studied. The researchers used standard testing methods to evaluate these various metrics, and it was discovered that some areas of cognitive function were more severely affected than others.


Cognitive Domain Affected by Indoor Air Quality

Cognitive Domain Affected by Indoor Air Quality

Brain Performance In Green vs Conventional Building

The charts above and below summarize the results. In almost every category the green and “green+” buildings outperform conventional and poorly ventilated spaces.

The most significant downgrades in mental performance were in Crisis Response, Information Usage, and Strategy. Makes you want every police station, school, hospital, and your very own home and office to be green, right?!?!  Does the White House Situation Room have sufficient ventilation and healthy materials? If not, does poor IAQ now constitute a national threat?

Indoor Air Quality and Brain Performance

Indoor Air Quality and Brain Performance


Indoor air quality and brain performance are obviously interconnected. If too many buildings across the US have insufficient ventilation and/or high levels of harmful VOCs and aldehydes, our nation will suffer in terms of crisis response and strategic thinking. Perhaps this helps explain some comments I’ve heard in recent political debates.

I pose that we add CO2 and VOCs to the priority terrorist list. They pose a clear and present danger to the US, and we should go after them with all we’ve got!


There is much more research needed, but I’m thrilled this small study received so much attention and I hope it leads to additional research and policy change. In the meantime we’ll keep encouraging our green building projects to achieve good ventilation and use healthier material alternatives.

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5 Responses to “Indoor Air Quality and Brain Performance”

  1. Dale C Rubin says :

    This performance have to be for long lasting otherwise there will be alot of problems of indoor air quality

  2. Alex Stadtner says :

    That’s a good question. There must be some studies showing how clutter affects performance and cognitive function… but I don’t know them.
    “Good housekeeping,” I suppose, should include tidying up! Good outside air ventilation is key, too.

  3. James Bergman says :

    I am really surprised that air quality can have such a big effect on cognitive functions. It makes me want to go home and deep clean my office so that I can work better there. I might even consider getting an air filter and clean my air ducts to make sure the air contamination is kept to a minimum. However, I do think that clutter does more to dampen my cognitive functions that air quality. Are there any studies on this?

  4. Andy Harrison says :

    That is really interesting to see the results of the tests. There is a correlation between brain function and the quality of air in the building. If I owned a business, then I would for sure see about getting cleaner air to help my employees work and perform better.

  5. Alex Trodder says :

    It makes sense that the indoor air quality can influence brain function. Our brain needs lots of oxygen to function properly, and CO2 levels can influence oxygen absorption rates in the blood. It sounds like this is something that businesses and homes need to consider to ensure that there is the highest level of productivity and safety. Thanks for sharing your research with us.

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