A bad air day

Recent research has concluded that the air quality in an office can seriously impact the focus and mental agility of those who work there. A study that included 300 office workers in six countries found that higher concentrations of fine particulate matter in the air and lower ventilation rates were associated with slower response times and reduced accuracy on cognitive tests.

The study mainly focused on a kind of pollution known as PM2.5, which is made up of particles under 2.5 micrometers long and is now known to be significantly damaging to our health. Whilst PM2.5 was the focus, the study also broadly looked at the levels of carbon dioxide, which were found to increase in poorly ventilated spaces.

Those who conducted the study commented that they had observed impaired cognitive function at concentrations of PM2.5 and carbon dioxide that were often detected indoors. The study also calls for a cut to the legal limits for particulate matter by more than half, as was laid out in The Times' campaign for a new Clean Air Act.

Two tests were used, both showing different things. The first required participants to identify the colour of words displayed on a computer screen: the word 'yellow' might appear, but in the colour green. The measure aims to tests cognitive speed and the ability to focus on relevant stimuli when irrelevant stimuli are also presented. The second test involved basic maths questions. The results were striking, with performance on the colour based test being markedly poorer when high levels of carbon dioxide and PM2.5 were present, whereas results on the maths-based test decreased in quality only when there was more carbon dioxide in the air.

This isn't the only study that has looked at a similar area though, with multiple studies being conducted in the past to show supporting results. One such example tracked 2,400 students on the day of their exams in a London University. It found that air quality in the hall on the day of the exam could have a sufficient impact to change the class of degree gained. Another study looking at 400,000 exams taken by Israeli teenagers showed that exams taken on relatively polluted days were associated with a 3% decline in students' test scores.

The latest research was published in Environmental Research Letters.