Poor Office Air Quality Impairs Workers’ Mental Faculty
GLOBAL – A new research by scientists at Harvard University that was published on Thursday in the Environmental Research Letters showed that poor indoor air quality in an office can debilitate staff’s mental faculties, including impairing ability to focus and slowing response time, reported Agence France-Presse (AFP) on Friday (10 September).
Notably, Jose Guillermo Cedeno Laurent, the study’s research fellow and lead author, and his colleagues designed a study that monitored 302 office workers in 6 nations over a period of 1 year until March 2020. The countries consist of the US, the UK, Thailand, Mexico, China, and India.
All participants were aged 18 to 65 who worked at least 3 days in an office building and had a permanent workstation there.
The researchers installed environmental sensors to track real-time concentrations of fine particulate matter 2.5 micrometres and smaller (PM2.5), in addition to temperature, relative humidity, and carbon dioxide levels.
The participants were provided with bespoke smartphone apps that tested their mental faculties during prescheduled times, or when sensors detected PM2.5 and CO2 levels that dropped below or surpassed certain thresholds.
Carbon dioxide concentrations serve as a proxy for ventilation levels. Outside, concentrations are roughly 400 parts per million (ppm), while 1000 ppm is regarded as an upper cap for indoor space.
The participants were asked to take 2 tests: The 1st one involved correctly identifying the colour of displayed text that spelled out a different colour. This assessed their cognitive speed and the capability to focus on relevant information amidst deceptive stimuli. In the 2nd task, the participants were asked to carry out basic addition and subtraction involving 2-digit numbers to evaluate their working memory & cognitive speed.
Ultimately, a gain of 10 micrograms per cubic meter of PM2.5 resulted in about 1 percent dip in response times for both tests and over 1 percent decline in accuracy.
For reference, the outdoor PM2.5 levels in Washington reached 13.9 micrograms per cubic meter on Thursday, while that in more polluted New Delhi hit 42 micrograms per cubic meter, based on data from IQAir tracking website.
In terms of carbon dioxide, an increase of 500 ppm, which is not an unusual level of variation, resulted in a decline in response time of over 1 percent, while the accuracy for both tests fell by more than 2 percent.
As such, Cedeno advises staff returning to their office with poor indoor air quality to open a window. But if the outdoor air quality is not good, he recommends upgrading the office building’s filtration systems or installing high quality portable air cleaners.
