Indoor air quality is something we talk a lot about at Precision-Aire. And there’s a good reason. According to a survey by the U.S. Environmental Protection Agency (EPA), Americans spend 87% of their time indoors—69% of their time at home, and 18% spent at another indoor location, such as an office or restaurant.
Knowledge workers—workers that typically work in an office and engage in creative and strategic work rather than traditional manufacturing and labor jobs—comprise an estimated 44% of U.S. workers, according to the 2013 book Practices for Engaging the 21st Century Workforce: Challenges of Talent Management in a Changing Workplace by William G. Castellano.
Intellectual capital, such as new product ideas or software code, is being increasingly viewed by organizations as an asset, an asset which improves the bottom line and should be protected and enhanced. Ideas, strategy, and productive capacity, become then, a company’s competitive advantage. And the factors that effect productivity for these knowledge workers, such as office air quality, are coming to the forefront.
John Mandyck, chief sustainability officer for the United Technologies Corporation (UTC) explains, “If you look at the true cost of operating a building, just one percent is energy. Ninety percent of the true operating cost of a building is the salaries and the benefits of the people inside the building. [If] green buildings can improve thinking, can improve productivity, can improve health, [then] buildings become human resource tools. Buildings can become ways that we can find competitive advantages simply by optimizing the indoor environmental quality.”
So how much does air quality really effect office worker productivity? As it turns out, according to a 2015 study published in Environmental Health Perspectives, quite a bit. Joe Allen of Harvard’s Center for Global Health and the Environment went as far as to the say the study’s results were “shocking.” (Full interview)
The study, which simulated the air quality conditions of a conventional office building, a green office building, and a green office building with enhanced ventilation, showed that the varying CO2 and VOC levels made significant impacts in the decision-making and cognition scores of the experiment’s subjects who spent time in the these buildings.
If your buildings contain a large ratio of knowledge-worker occupants or organizations who derive their competitive edge from strategy, crisis management, and a high level of productive and creative output, then indoor air quality should be top-of-mind for you as well.
The 2015 Syracuse Cognition & Green Building Study
The most interesting thing about this air quality study said Joe Allen in an interview, is that it wasn’t testing “anything exotic…We didn’t introduce chemicals into the environment that you don’t typically encounter; we didn’t introduce ventilation rates that are impossible to obtain. The idea was to simulate office environments that can easily be obtained. What’s shocking is that you see this big effect and the effort it takes to reach it wasn’t that much.”
The study took place at the Syracuse Center of Excellence, where 24 random office workers were recruited as participants to work their typical 9 am–5 pm workday inside what looked to be an average office building, filled with cubicles, desks, computers, phones, and photocopiers.
Unbeknownst to the workers, the building was wired and ducted for a nearly futuristic control over the building’s indoor air quality. Over the 6 day period, which spanned two weeks, scientists were able to independently and simultaneously test metrics such as carbon dioxide (CO2) levels, volatile organic compound (VOC) levels, and ventilation rates (VRs). High VOC levels simulated the conventional office and low VOC levels represented the Green office. And the “Green+” building was simulated with low VOC levels and a higher outdoor ventilation rate. High levels of CO2 were also tested separately from the simulations.
At the end of each day, the workers took a 1.5 hour cognitive test that assessed decision-making in real-life situations and analyzed nine “functional domains:”
- basic activity level (number of actions taken)
- applied activity (opportunistic actions)
- focused activity (strategic actions in a narrow endeavor)
- task orientation (focus on concurrent task demands)
- initiative (development of new/creative activities)
- information search (openness to and search for information)
- information usage (ability to use information effectively)
- breadth of approach (flexibility in approach to the task)
- basic strategy (number of strategic actions)
According to the study’s published paper entitled: “Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers: A Controlled Exposure Study of Green and Conventional Office Environments”:
On average, cognitive scores were 61% higher on the Green building day and 101% higher on the two Green+ building days than on the Conventional building day.
Indoor Air Quality Metrics that Effect Employee Cognition
Carbon Dioxide (CO2)
Indoor levels of carbon dioxide (CO2) are determined by indoor occupant respiration, which can be managed through ventilation rates and tightness of building envelope design. The indoor CO2 baseline is effected by the outdoor carbon dioxide level, which changes with automobile exhaust levels, industrial pollution, and other types of combustion.
CO2 was, until recently, thought of as a benign substance for human inhalation, with little to no adverse effects, and used only as a marker for measuring ventilation rates (VRs) and concentrations of volatile organic compounds (VOCs). Carbon dioxide, though, when tested separately from ventilation and VOCs, was found by a 2012 study published in Environmental Health Perspectives to significantly impact decision-making ability and work performance speed at levels as little as 1000 and 2500 ppm. In contrast, the Occupational Safety and Health Administration (OSHA) allows up to 5000 ppm of carbon dioxide as a time-weighted average in an 8-hr workday.
Volatile Organic Compounds (VOCs)
Volatile organic compounds (VOCs) are airborne particles that evaporate or sublimate from the liquid or solid version of the chemical. This evaporation or sublimation at room temperature is what makes the compounds “volatile.” VOCs are ubiquitous in modern life, found in a variety of natural and manufactured everyday products such as paint, upholstery, composite wood products, second-hand smoke, carpets, vinyl floors, cleaning chemicals and more. Most odors, for instance that “new car smell,” are actually the smell of VOCs. According to the Minnesota Department of Health, indoor VOC levels can be 2-5 times higher than outdoor levels.
In the 2015 green building and cognition study, the total VOC (TVOC) level of <50 µg/m3 was constant on all days except the days chosen to simulate the conventional building environment, when levels were increased to 506–666 µg/m3. On low VOC days (Green building and Green+ building days), general cognitive scores were 61% and 101% higher, respectively, than the conventional building days. Crisis response, information usage, and strategy were most effected by VOC-levels, with cognition scores increasing at much as 299%, as it did for the information usage score on Green+ days.
Ventilation rate (VR) is the rate at which indoor air is exchanged with outdoor air and is expressed in cubic feet per minute (CFM) per person. Currently, ASHRAE 62.1 requires a minimum of 20 cfm/person, which is equivalent to an indoor carbon dioxide concentration of 945 ppm.
In the 2015 green building and cognition study, outdoor ventilation rates remained 20 cfm/person for the conventional and green building days and were increased to 40 cfm/person on the Green+ days. In general, participants increased cognitive scores by 25% when ventilation rates increased.
Action Steps To Improve Cognition-Related Air Quality Metrics
Measure Your Starting Point
“If you can measure it, you can manage it,” the old saying goes. If you haven’t already, create an IAQ profile for your building. A full profile is always best, but if you are particularly interested in the cognition-related metrics exposed by this study, make sure to note:
Current number of occupants
- Whether the number of occupants has changed since the HVAC equipment was installed (thereby effecting CO2 concentrations)
- Current ventilation rates
- Purposeful or accidental blocking of vents or air returns, which effects proper ventilation
- Using a handheld monitor like the Extech Indoor Air Quality Carbon Dioxide Meter log CO2 levels in a variety of locations throughout the building, at different times, focusing on offices
- Locations of high CO2 areas (for instance garages or loading docks)
- Outdoor levels of CO2
- Possible building envelope infiltration areas from areas of high CO2 to office areas
- Using a handheld monitor like the E Instruments AQ VOC Air Quality Monitor (http://www.tequipment.net/E-Instruments/AQ-VOC/Indoor-Air-Quality-Monitors/) measure VOC levels throughout the building and day over a period of time
- Locations of recent construction or equipment installation, which will likely have increased VOC levels
- Sources of VOCs present in your buildings, for instance photocopiers, printers, stored paints and solvents, carpeting, drywall, and vinyl floors
- Locations of smoking areas
- Locations of persistent odors
- If time or equipment resources are minimal, consider contacting a qualified IAQ assessment company to do a baseline analysis
Develop An IAQ Management Plan
- Schedule recurring check-ins with tenants and landlords to update your building profile baseline. Has occupancy changed? New equipment? New construction?
- Set up an ongoing schedule to monitor and record VOC and CO2 levels and ventilation rates
- Log HVAC and IAQ complaints
- Determine IAQ improvements to be made and schedule work to be done
- Set up a recurring scheduling for cleaning and maintenance
Consider These IAQ Improvements
- Upgrade cleaning chemicals to “green” cleaners
- Increase ventilation rates
- Remove smoking zones entirely, or, if unrealistic, move zones to areas of the building that minimize building envelope infiltration
- Remove or consider storing high-VOC chemicals (like paint and solvents) off-site
- Add additional ventilation ducts to areas with persistent low air exchange rates
- If remodeling or construction is planned, choose products with low levels of VOC off-gassing such as tile instead of vinyl flooring, or specialized low-VOC paint
- Replace old carpet with carpet with the Carpet and Rug Institute (CRI) Green Label
- Most HVAC systems, designed to heat and cool indoor spaces, are not equipped to filter air for VOCs. Consider adding a photocatalytic filter or granular activated carbon (GAC) filter to the HVAC system to reduce VOC levels.
- Switch to a CO2-based demand controlled ventilation (DCV) HVAC system. These systems allow for increased ventilation based on CO2 levels in addition to saving energy by decreasing ventilation when the space is not occupied.
Need advice on your particular IAQ situation? We’d love to help. Contact us today.