Studies such as Oxford Brookes University and LCMB (2018) showed significant impacts on the effects of CO₂ levels on productivity. The two-year research exercise which looked at various types of workplace, used sensors to monitor CO₂ level fluctuations over the time of the study. Employees carried out numerical, proofreading and Stroop tests. The results were striking; employees worked up to 60% faster when exposed to lower levels of CO₂, and their test scores improved by up to 12%.

In Zs. Bakó-Biró, et al’s 2011 paper Ventilation rates in schools and pupils’ performance the effects of classroom ventilation on pupils’ performance were investigated in 8 primary schools in England. In each school the concentrations of carbon dioxide and other parameters were monitored for three weeks in two selected classrooms. In 16 classrooms interventions were made to improve the ventilation rate and maintain the temperature within an acceptable range using a purpose-built portable mechanical ventilation system. The results of computerized performance tasks performed by more than 200 pupils showed significantly faster and more accurate responses for Choice Reaction (by 2.2%), Colour Word Vigilance (by 2.7%), Picture Memory (by 8%) and Word Recognition (by 15%) at the higher ventilation rates compared with the low ventilation conditions.

In their 2014 paper Classroom carbon dioxide concentration, school attendance, and educational attainment Gaihre, Semple, Miller, Fielding and Turner presented the results of an investigation into the impact of carbon dioxide on absence rates in schools. They found significant impact of CO₂ in an intervention-based study where it was discovered that absence rates decreased by 0.4 days per year for each 100 ppm decrease in CO₂ concentration. To put this in context many studies have discovered long term exposure of over 4000 ppm in a number of schools, which is 3600 ppm above outdoor baseline. Long term exposure to this level of CO₂ has significant impact on the health of the children within the classroom.

Optimising the CO₂, temperature and humidity within your office has a direct impact on the comfort experienced by building inhabitants. Exposing building inhabitants to carbon dioxide levels between 1000 ppm and 1500 ppm will result in complaints of stuffiness. A level of between 500 and 750 ppm may be achievable in well ventilated building which doesn’t have a high density of inhabitants when well managed.

Sustained exposure to CO₂ levels of 2000ppm or above can result in reported health impacts such as drowsiness and headaches. Reducing the carbon dioxide levels in a room also has other positive impacts such as reducing other unwanted particles from the air such as pollutants and airborne viruses. Carbon Dioxide (CO₂) concentrations can be used as a proxy for ventilation rate with 3 L/s being equivalent to 2100 ppm of CO₂ under equilibrium conditions. Prolonged exposure to levels of 5,000ppm or above can result in long term negative health impacts.

High levels of humidity resulting in condensation and mould growth which generally stems from poor ventilation is a problem in social housing which generally results from poor ventilation. If left unaddressed this can ultimately lead to damage to the building’s fabric and serious health problems such as respiratory disorders for its residents. Of the social housing homes in England 205,000 have damp in one or more rooms.