The Effect of Indoor Temperature and CO2 Levels on Cognitive Performance of Adult Females in a University Building in Saudi Arabia

Temperatures and indoor CO2 levels within buildings play a crucial role, not only for energy consumption, but also for occupant performance and particularly cognitive performance regarding all mental activities such as thinking, reasoning, and remembering. Using a multi-variable multilevel approach, the effects of classroom temperature and CO2 levels were estimated on vigilance and memory tasks. The analysis is based on two classrooms' physical environmental measurements data in a university located in Saudi Arabia. Participant votes on standard subjective thermal rating scales were collected from 499 adult female students, which were correlated with relevant environmental parameters such as humidity, radiant temperature, air velocity and self-reported clothing levels. Performance against two neurobehavioral cognitive tests was evaluated. The effects of three temperature levels were investigated. Statistically significant associations were observed between the cognitive test outomes and the investigated exposure conditions of classrooms' temperature and CO2 concentration levels. The associations remained significant after adjusting for confounding variables.