Investigating the Impact of (CO₂) Concentration and Healthcare Architecture on Staff Fatigue and Thermal Comfort

Abstract :

Poor indoor air quality and elevated CO₂ levels in healthcare environments—due to inadequate ventilation and unfavorable environmental conditions—can compromise thermal comfort and endanger staff health. Appropriate architectural design, including optimized ventilation, daylighting, and spatial organization, can help prevent CO₂ buildup, reduce fatigue, and enhance staff performance.The aim of this study was to examine the effect of elevated CO₂ concentrations on staff fatigue and thermal comfort in healthcare facilities. An experimental study was conducted in a specialized clinic in Ilam, Iran. The study population consisted of 20 healthcare staff members working in a basement-level laboratory. Participants were randomly assigned to exposure to two different CO₂ concentrations: 1100 ppm with mechanical ventilation and 1800 ppm without mechanical ventilation.During exposure, heart rate measurements, thermal comfort assessments (using the ASHRAE standard questionnaire), and fatigue evaluations (using the standardized Multidimensional Fatigue Inventory, MFI) were recorded. Data were analyzed using Multivariate Analysis of Covariance (MANCOVA).Findings revealed that higher CO₂ concentrations (1800 ppm without ventilation compared to 1100 ppm with ventilation) had a significant impact on general, physical, and mental fatigue, as well as a decrease in staff activity and motivation (p < 0.05). Furthermore, thermal discomfort during work activities significantly contributed to general, physical, and mental fatigue (p < 0.05). Increased heart rate was also significantly associated with general fatigue and reduced activity and motivation (p < 0.05). However, the interaction effects between these factors were not statistically significant (p > 0.05).Among the various dimensions of fatigue, general fatigue emerged as the most influential factor, followed by physical and mental fatigue.According to ASHRAE standards and the results of this study, elevated CO₂ concentrations (1800 ppm vs. 1100 ppm) in healthcare environments can adversely affect fatigue levels and thermal comfort, potentially leading to serious long-term health issues for staff. The findings also demonstrated that higher CO₂ levels cause thermal discomfort, elevated heart rates, and increased general, physical, and mental fatigue, ultimately reducing staff activity and motivation.Thus, implementing effective ventilation systems and continuous monitoring of indoor air quality are essential strategies for enhancing staff performance and safeguarding the health of employees in healthcare environments.

References:

1- Alsayed, S. A., Abou Hashish, E. A., & Alshammari, F. (2022). Occupational fatigue and associated factors among Saudi nurses working 8-hour shifts at public hospitals. SAGE open nursing, 8, 23779608221078158.doi:10.1177/23779608221078158
2- ASHRAE, ASHRAE Handbook-HVAC applications (SI). 2019: Atlanta
3- Bazazan, A., Dianat, I., Mombeini, Z., Aynehchi, A., & Jafarabadi, M. A. (2019). Fatigue as a mediator of the relationship between quality of life and mental health problems in hospital nurses. Accident Analysis & Prevention,126,31-36.doi:10.1016/j.aap.2018.01.042
4- Building Energy Research Center, Tsinghua University. 2020 report Annual Report on China Building Energy Efficiency (in Chinese) (China Architecture & Building Press, Beijing, 2020).
5- Carswell, C. M., Clarke, D., & Seales, W. B. (2005). Assessing mental workload during laparoscopic surgery. Surgical innovation, 12(1), 80-90. doi:10.1177/155335060501200112
6- Chen, J., Davis, K. G., Daraiseh, N. M., Pan, W., & Davis, L. S. (2014). Fatigue and recovery in 12‐hour dayshift hospital nurses. Journal of nursing management, 22(5), 593-603. doi:10.1111/jonm.12062
7- Chen, Y., Tao, M., & Liu, W. (2020). High temperature impairs cognitive performance during a moderate intensity activity. Building and Environment, 186, 107372. doi:10.1016/j.buildenv.2020.107372
8- Cohen, T. N. (2017). A human factors approach for identifying latent failures in healthcare settings. https://commons.erau.edu/edt/290
9- de Souza, L. P., Bracht, M. K., Bavaresco, M., Geraldi, M. S., Gapski, N., Boudier, K., Melo, A. P., & Hoffmann, S. (2024). Thermal sensation and adaptation after spatial transition: a review and meta-analysis. Building and Environment, 111585. doi:10.1016/j.buildenv.2024.111585
10- Eldevik, M. F., Flo, E., Moen, B. E., Pallesen, S., & Bjorvatn, B. (2013). Insomnia, excessive sleepiness, excessive fatigue, anxiety, depression and shift work disorder in nurses having less than 11 hours in-between shifts. PloS one, 8(8), e70882. doi:10.1371/journal.pone.0070882
11- Energy Information Administration. International Energy Outlook 2016. Washington D.C.: EIA (2016)
12- Epstein, L. H., Paluch, R. A., Kalakanis, L. E., Goldfield, G. S., Cerny, F. J., & Roemmich, J. N. (2001). How much activity do youth get? A quantitative review of heart-rate measured activity. Pediatrics, 108(3), e44-e44. doi:10.1542/peds.108.3.e44
13- Fan, X., & Zhu, Y. (2024). Effects of indoor temperature on office workers’ performance: an experimental study based on subjective assessments, neurobehavioral tests, and physiological measurements. Ergonomics, 67(4), 526-540. doi:10.1080/00140139.2023.2231181
14- Farhadi, F. Khakzand, M. Barzegar, Z.etal.(2024) Investigating parameters affecting indoor air quality in healthcare spaces. Sadra Medical Sciences Journal. 12(2): 151.
15- -Fatahi K, Beigi M. Assessing the state of cognitive performance of employees and determining the range of thermal comfort of different genders in Ilam hospitals. tkj 2024; 16 (3) :27-41
16- Fujii, H., Fukuda, S., Narumi, D., Ihara, T., & Watanabe, Y. (2015). Fatigue and sleep under large summer temperature differences. Environmental Research, 138, 17-21. doi:10.1016/j.envres.2015.02.006
17- Garrouste-Orgeas, M., Philippart, F., Bruel, C., Max, A., Lau, N., & Misset, B. (2012). Overview of medical errors and adverse events. Annals of intensive care, 2, 1-9. doi:10.1186/2110-5820-2-2
18- GAUTHIER, S., LIU, B., HUEBNER, G., & SHIPWORTH, D. (2015). Investigating the effect of CO2 concentration on reported thermal comfort. Proceedings of International Conference CISBAT 2015 Future Buildings and Districts Sustainability from Nano to Urban Scale,
19- Ho, J.-C., Lee, M.-B., Chen, R.-Y., Chen, C.-J., Chang, W. P., Yeh, C.-Y., & Lyu, S.-Y. (2013). Work-related fatigue among medical personnel in Taiwan. Journal of the Formosan Medical Association, 112(10), 608-615. doi:10.1016/j.jfma.2013.05.009
20- Karimi, A., Bayat, A., Mohammadzadeh, N., Mohajerani, M., & Yeganeh, M. (2023). Microclimatic analysis of outdoor thermal comfort of high-rise buildings with different configurations in Tehran: Insights from field surveys and thermal comfort indices. Building and Environment, 240, 110445. doi:10.1016/j.buildenv.2023.110445
21- Kim, J., Kong, M., Hong, T., Jeong, K., & Lee, M. (2018). Physiological response of building occupants based on their activity and the indoor environmental quality condition changes. Building and Environment, 145, 96-103. doi:10.1016/j.buildenv.2018.09.018
22- Kulczycka, K., Grzegorczyk-Puzio, E., Stychno, E., Piasecki, J., & Strach, K. (2016). Wpływ pracy na samopoczucie ratowników medycznych. Medycyna Ogólna i Nauki o Zdrowiu, 22(1).
23- Liang, Y., Yu, J., Xu, R., Zhang, J., Zhou, X., & Luo, M. (2024). Correlating working performance with thermal comfort, emotion, and fatigue evaluations through on-site study in office buildings. Building and Environment, 265, 111960.doi:10.1016/j.buildenv.2024.111960
24- Liu, W., Zhang, T. T., & Lai, D. (2023). Inverse design of a thermally comfortable indoor environment with a coupled CFD and multi-segment human thermoregulation model. Building and Environment, 227, 109769. doi:10.1016/j.buildenv.2022.109769
25- Liu, W., Zhong, W., & Wargocki, P. (2017). Performance, acute health symptoms and physiological responses during exposure to high air temperature and carbon dioxide concentration. Building and Environment, 114, 96-105. doi:10.1016/j.buildenv.2016.12.020
26- -MacDonald, W. (2003). The impact of job demands and workload on stress and fatigue. Australian psychologist, 38(2), 102-117. doi:10.1080/00050060310001707107
27- Mahdavi, N., Dianat, I., Heidarimoghadam, R., Khotanlou, H., & Faradmal, J. (2020). A review of work environment risk factors influencing muscle fatigue. International journal of industrial ergonomics, 80, 103028. doi:10.1016/j.ergon.2020.103028
28- Martins, L. A., Soebarto, V., & Williamson, T. (2022). A systematic review of personal thermal comfort models. Building and Environment, 207, 108502.
29- Matuz, A., van der Linden, D., Kisander, Z., Hernadi, I., Kazmer, K., & Csatho, A. (2021). Enhanced cardiac vagal tone in mental fatigue: Analysis of heart rate variability in Time-on-Task, recovery, and reactivity. PloS one, 16(3), e0238670. doi:10.1371/journal.pone.0238670
30- Maula, H., Hongisto, V., Naatula, V., Haapakangas, A., & Koskela, H. (2017). The effect of low ventilation rate with elevated bioeffluent concentration on work performance, perceived indoor air quality, and health symptoms. Indoor air, 27(6), 1141-1153.doi:10.1111/ina.12387
31- -Mirmohammadi, S., Mehrparvar, A., Kamali, Z., & Mostaghaci, M. (2011). Evaluation or the relationship between shift work and sleepiness in nurses. Occupational Medicine Quarterly Journal, 3(2), 31-38.
32- Ramdan, I. M. (2019). Measuring work fatigue on nurses: a comparison between indonesian version of Fatigue Assessment Scale (FAS) and Japanese Industrial Fatigue Ressearch Commite (JIFRC) Fatigue Questionnaire. Jurnal Keperawatan Padjadjaran, 7(2), 143-153. doi:10.24198/jkp.v7i2.1092
33- Singer, B. C. (2009). Hospital Energy Benchmarking Guidance-Version 1.0.
34- Solano, J. C., Caamaño-Martín, E., Olivieri, L., & Almeida-Galárraga, D. (2021). HVAC systems and thermal comfort in buildings climate control: An experimental case study. Energy Reports, 7, 269-277. doi:10.1016/j.egyr.2021.06.045
35- Tanabe, S.-i., Nishihara, N., & Haneda, M. (2007). Indoor temperature, productivity, and fatigue in office tasks. Hvac&R Research, 13(4), 623-633.
36- Techera, U., Hallowell, M., Stambaugh, N., & Littlejohn, R. (2016). Causes and consequences of occupational fatigue: meta-analysis and systems model. Journal of occupational and environmental medicine, 58(10), 961-973.
37- Tu, Z., Li, Y., Geng, S., Zhou, K., Wang, R., & Dong, X. (2021). Human responses to high levels of carbon dioxide and air temperature. Indoor air, 31(3), 872-886. doi:10.1111/ina.12769
38- Vehviläinen, T., Lindholm, H., Rintamäki, H., Pääkkönen, R., Hirvonen, A., Niemi, O., & Vinha, J. (2016). High indoor CO2 concentrations in an office environment increases the transcutaneous CO2 level and sleepiness during cognitive work. Journal of occupational and environmental hygiene, 13(1), 19-29.
39- Wickens, C. D. (2008). Multiple resources and mental workload. Human factors, 50(3), 449-455.
40- Wilson, M. R., Poolton, J. M., Malhotra, N., Ngo, K., Bright, E., & Masters, R. S. (2011). Development and validation of a surgical workload measure: the surgery task load index (SURG-TLX). World journal of surgery, 35, 1961-1969.
41- Wu, J., Lian, Z., Zheng, Z., & Zhang, H. (2020). A method to evaluate building energy consumption based on energy use index of different functional sectors. Sustainable Cities and Society, 53, 101893. doi:10.1016/j.scs.2019.101893
42- Yang, L., Yan, H., & Lam, J. C. (2014). Thermal comfort and building energy consumption implications–a review. Applied energy, 115, 164-173.
43- Yang, L., Zhao, S., Zhai, Y., Gao, S., Wang, F., Lian, Z., Duanmu, L., Zhang, Y., Zhou, X., & Cao, B. (2023). The Chinese thermal comfort dataset. Scientific Data, 10(1), 662. doi:10.1038/s41597-023-02568-3
44- Yuan, F., Yao, R., Sadrizadeh, S., Li, B., Cao, G., Zhang, S., Zhou, S., Liu, H., Bogdan, A., & Croitoru, C. (2022). Thermal comfort in hospital buildings–A literature review. Journal of Building Engineering, 45, 103463. doi:10.1016/j.jobe.2021.103463
45- Zhang, J., Cao, X., Wang, X., Pang, L., Liang, J., & Zhang, L. (2021). Physiological responses to elevated carbon dioxide concentration and mental workload during performing MATB tasks. Building and Environment, 195, 107752. doi:10.1016/j.buildenv.2021.107752
46- Zhang, J., Pang, L., Cao, X., Wanyan, X., Wang, X., Liang, J., & Zhang, L. (2020). The effects of elevated carbon dioxide concentration and mental workload on task performance in an enclosed environmental chamber. Building and Environment, 178, 106938. doi:10.1016/j.buildenv.2020.106938
47- Zheng, P., Liu, Y., Wu, H., & Wang, H. (2024). Non-invasive infrared thermography technology for thermal comfort: A review. Building and Environment, 248, 111079. doi:10.1016/j.buildenv.2023.111079
48- Zhou, S., Li, B., Du, C., Liu, H., Wu, Y., Hodder, S., Chen, M., Kosonen, R., Ming, R., & Ouyang, L. (2023). Opportunities and challenges of using thermal comfort models for building design and operation for the elderly: A literature review. Renewable and Sustainable Energy Reviews, 183, 113504. doi:10.1016/j.rser.2023.113504