Investigating the Effect of Carbon Dioxide in the Air on the Feeling of Thermal Comfort, Cognitive Function, and Heart Rate of Healthcare Workers while Working

Objectives: The primary aim of this study is to examine the impact of carbon dioxide (CO2) concentrations in the air on thermal comfort, cognitive performance, and heart rate among healthcare workers while they engage in their duties within therapeutic environments. These settings are often characterized by high occupancy, inadequate ventilation, underground locations, limited natural light, and exposure to pollutants. Methods: In this laboratory-based research, 20 employees from a specialized clinic were randomly assigned into two groups of ten. They were exposed to varying levels of CO2 at a controlled temperature of 25°C: one group experienced 1100 ppm with adequate ventilation, while the other was subjected to 1800 ppm without ventilation. Key parameters, such as heart rate, thermal comfort (assessed using the ASHRAE standard questionnaire), and cognitive performance (measured through the MOCA test) were recorded. The collected data were analyzed using multivariate analysis of covariance (MANCOVA). Results: The statistical analysis revealed significant effects of cognitive performance and CO2 levels (1800 ppm vs. 1100 ppm) on thermal comfort (F(1,15)=13.257, P<0.05 and F(1,15)=16.694, P<0.05). Furthermore, both the CO2 levels and the gender of participants significantly influenced the heart rate of healthcare workers in their work environments (F(1,15)=53.381, P<0.05 and F(1,15)=9.642, P<0.05). Specifically, individuals exposed to 1800 ppm of carbon dioxide reported a thermal dissatisfaction score that was 0.878 units higher and exhibited a heart rate that was 9.25 beats per minute greater compared to those exposed to 1100 ppm. Conclusion: The findings underscore the importance of continuous air quality monitoring in workplace settings. Such measures can enhance thermal comfort levels, improve cognitive performance, and mitigate health risks for healthcare workers engaged in their professional activities