Air Quality and Temperature

Hviid et al. (2020) conducted a field lab study to examine the influence that indoor ventilation and lighting had on children’s academic abilities. The study included 92 children who were between 10 and 12 years old and lasted for four weeks in a school in Valby, Denmark. Over the course of the 4-week study, students completed a questionnaire and three different performance tests, which measured processing speed, concentration, logical reasoning, and math solving abilities. To evaluate the cognitive processes of the students, three tests were used. The d2-test is a cancellation task that evaluates the visual scanning speed of an individual and measures how well focus can be kept on a task. The Baddeley test was used to measure logical reasoning. It involves the understanding of sentences of various levels of complexity, giving quick feedback on an individual’s ability to think logically and sensibly. In the math test, students solved multiplication and subtraction questions. A questionnaire was also completed after each Baddeley-test to determine the students’ perceptions of the indoor environment. The results of the study showed that processing speed, concentration, and math skills improved the most in the scenario with high ventilation rates and cool lighting.

A meta-analysis from Wargocki et al. (2019) detailed published evidence on the impact that temperature in school classrooms has on students’ performance. Data from 18 different studies were used to construct a relationship between classroom temperatures and children’s performance in school. Literature was surveyed to find studies that examined the impact of thermal conditions in the classroom on student performance. The inclusion criteria for articles were that they must have reported both measurements of thermal environment and measurements of the performance of schoolwork or of learning outcomes. Only studies conducted with students younger than 19 years old were used. Psychological tests measuring cognitive abilities, school tasks, tests, and rating schemes were all examples of indicators of student performance. Thermal conditions were simply characterized by measured classroom temperatures. To create the relationship between student performance and temperature, “the fractional change in performance of psychological tests and school tasks was regressed against the average temperature at which the change was recorded; all published data were used regardless of whether the change in learning outcome changed significantly with temperature” (Wargocki et al., 2019, p. 198). The relationship determined from the analysis demonstrated that student performance of psychological tests and school tasks increased on average by 20% if classroom temperatures were dropped from 30 °C to 20 °C.

The analysis from Wargocki et al. (2019) also showed that the optimal temperature for performance is lower than 22 °C.

The results from Wargocki et al. (2019) also demonstrated that the impact of classroom temperature on cognitive performance is not negligible and that the impact on students is much higher than it is for adults in office settings. It is worth noting that the relationship between temperature and classroom performance that was constructed by Wargocki et al. (2019) is only valid for temperate climates. Temperate climates occur in the mid-latitudes between the tropics and polar regions, where summers are mild to warm, and winters are cool to cold.

A literature review from Wolfoff et al. (2021) summarized some useful information related to air quality. Low indoor air humidity can cause an elevation in mucous membrane-related symptoms such as dry and tired eyes. This is due to less efficient mucociliary clearance caused by the low indoor air humidity. Proper ventilation can reduce both acute and chronic health outcomes, while also improving work performance, which is due to reduced exposure to indoor air pollutants.

According to the previously mentioned literature review from Wolfoff et al. (2021).

According to the previously mentioned literature review from Wolfoff et al. (2021).

Carrer et al. (2015) reviewed scientific literature to determine the connection between building ventilation and health (disease) outcomes. This review determined that, in general, higher ventilation rates will often reduce negative health outcomes. However, they were not able to determine an air ventilation rate that could be universally applicable within different buildings, as the literature showed a range of ventilation rates that provided positive benefits.

There does not seem to be a universally applicable ventilation rate between different buildings that is beneficial. Though this is a wide range, Carrer et al. (2015) were able to determine that overall, an increase in ventilation rates had positive results.

Higher ventilation rates were beneficial to those with asthma and allergies. Increased ventilation rates can also reduce the onset of acute health symptoms. An example of this is a reduction in mucosal symptoms, which includes dry eyes, sore throat, sore nose/sinus, and sneezing. A 1000 ppm increase in CO2 above outdoor levels due to a lower ventilation rate was associated with a 10-20% increase in student absence (Carrer et al., 2015).

According to the previously mentioned literature review from (Carrer et al., 2015).