Impact of Indoor Environmental Quality on Student Behavior: A Case Study Using AI-Powered Computer Vision.

This paper investigates the Indoor Environmental Quality (IEQ) factors influencing occupant satisfaction in commercial buildings in Iran, contrasting the views of building experts (architects and engineers) with those of building occupants. Employing the fuzzy analytical hierarchy process (FAHP), this study focuses on the four primary IEQ factors: thermal comfort, indoor air quality, visual comfort, and acoustic comfort. The study aims to bridge the gap between expert evaluations and occupant perceptions of IEQ factors in commercial buildings in Iran. By examining the disparities in prioritising IEQ factors between these two groups, the study sheds light on the complexities of IEQ assessment and highlights the importance of considering diverse perspectives in optimising indoor environments. Our methodology includes a survey conducted among 30 building experts (15 architects and 15 building engineers) and 102 occupants, employing FAHP to derive the relative importance weights of each IEQ factor. The results highlight significant disparities between architects, engineers, and occupants in prioritising these factors. Architects emphasise visual comfort (42%), while engineers and occupants view thermal comfort (53% and 41%) as the most crucial factor for occupant satisfaction. The study underscores the complexity of IEQ in commercial buildings and the diverse perspectives influencing its assessment. It contributes to the broader discourse on optimising IEQ, emphasising the need for a comprehensive approach that encompasses both technical expertise and occupant experience.

This study investigates the impact of indoor environmental quality (IEQ) factors—thermal environment, indoor air quality, lighting, and acoustics—on university students' satisfaction. Conducted at University College London (UCL), the research employs a mixed-method approach, combining subjective assessments through questionnaires with objective measurements of environmental conditions. The findings reveal that students exhibit higher satisfaction with cooler indoor environments during spring, with thermal comfort significantly influencing their overall satisfaction. Indoor air quality, particularly air movement and relative humidity, also plays a crucial role, with students preferring neutral conditions. Acoustic and lighting environments further impact satisfaction, with a notable preference for brighter lighting despite overall contentment with current levels. The study underscores the complex interplay between various IEQ factors and their collective influence on students' well-being, highlighting the need for tailored environmental designs in educational settings to enhance student satisfaction.

Post-occupancy evaluation is a well-known research method documenting occupants’ satisfaction with indoor environmental quality (IEQ) factors. Despite potentially significant roles of gender differences in IEQ satisfaction, it has not always been acknowledged by researchers and findings are debated. Through a self-administered questionnaire over nine years, students (n = 3140) in 11 different higher education classroom buildings in Minnesota, USA rated their satisfaction with 23 IEQ factors. They were most satisfied with overall cleaning and maintenance followed by overall indoor air quality and amount of electric lighting. Students were least satisfied with access to electric outlets followed by daylighting IEQ factors. Mann–Whitney U tests showed that female students were statistically less satisfied with overall thermal conditions and temperature, while male students were statistically less satisfied with daylighting, electric lighting, and view conditions. Subsequent logistic regression analyses indicated the most significant impact of amount of electric lighting. The results imply that once students were dissatisfied with amount of electric lighting, they were more likely to be dissatisfied with the classroom. Despite the significant impacts of all IEQ factors, the different degree of the likelihoods indicates that some IEQ factors may impact classroom satisfaction more than other IEQ factors as indicated by this benchmark study.

• Assesses the asymmetric effects of IEQ on guest ratings of hotels and apartments. • Most IEQ factors act as Basic Factors, critical for avoiding dissatisfaction. • Exterior view is an Excitement Factor in budget hotels but Basic in luxury ones. • COVID-19 heightened sensitivity to cleanliness, air quality, views and space adequacy. • IEQ can explain 32.8% of guest ratings in budget accommodations and 23.9% in luxury ones. Guest satisfaction is pivotal for the hospitality industry, yet the role of Indoor Environmental Quality (IEQ) in shaping guest ratings remains inadequately explored. This study addresses this gap by leveraging web-mining, natural language processing and the Three-Factor Theory to analyse guest reviews of Australian hotels and serviced apartments listed on Booking.com. Findings indicate that most IEQ factors—thermal comfort, indoor air quality, luminous environment, acoustics, space, facilities, cleanliness, and layout—function as Basic Factors. While deficiencies in these areas drive dissatisfaction, their adequacy alone does not significantly enhance satisfaction. Notably, exterior view serves as an Excitement Factor in budget accommodations (three stars or below) but transitions to a Basic Factor in luxury settings. Among all IEQ factors, cleanliness, indoor air quality, and acoustics had the strongest negative impacts when underperforming, whereas satisfactory exterior views, cleanliness, and available space positively influenced guest ratings. The COVID-19 pandemic intensified these effects, heightening guest sensitivity to IEQ deficiencies (e.g., poor air quality) while elevating expectations for high-performing attributes like exterior views and available space. Overall, IEQ factors accounted for 32.8% of customer ratings in budget hotels and 23.9% in luxury accommodations. The findings underscore the necessity of ensuring satisfactory performance across all IEQ factors, particularly cleanliness and indoor air quality, while strategically enhancing exterior views and spatial configuration to optimize guest satisfaction. These insights provide hospitality managers and policymakers with data-driven guidance for enhancing guest satisfaction and operational resilience in post-pandemic hospitality settings.

Assessing the impact of environmental quality factors on the industrial performance of aged workers: A literature review

Post-occupancy evaluations (POE) have been often used to study user satisfaction with office environments. More recently, POEs have been recognized for documenting occupant well-being and responses to 26 indoor environmental quality (IEQ) factors that incorporate sustainable design guidelines such as thermal, lighting, and acoustic conditions. The Sustainable Post-Occupancy Evaluation Surveys (SPOES) have measured occupants’ (n = 2836) satisfaction with IEQ factors for 11 years. This paper presents findings from this 11-year-benchmark study. It suggests a lower satisfaction rating for adjustability than other IEQ factors. Based on further logistic regression analyses of the IEQ factors, occupants tended to be dissatisfied with their primary workspace when they were dissatisfied with acoustic conditions, furnishings, and privacy. The results imply that improving acoustic and privacy conditions, especially, would bring the most significant impact on the positive experience in built environments, whereas improving thermal conditions would impact relatively less significant on the positive experience. Acknowledging how differently each IEQ factor can affect building occupants’ satisfaction and perception is important for determining benchmarks that support occupants’ health and well-being in the workplace environment, where they spend much of their time.

How indoor environmental quality affects occupants’ cognitive functions: A systematic review

Satisfaction is a very important factor in improving productivity and performance in the work environment. This study aims to investigate the levels of occupants’ satisfaction with the indoor environmental quality (IEQ) in the governmental buildings in the Kingdom of Bahrain and to investigate the impact of occupants’ demographics and building attributes (non-IEQ factors) on these levels. For these purposes, the study used a questionnaire that has 17 indoor environmental quality (IEQ) factors in addition to a group of non-IEQ factors. The questionnaire was distributed by hand or using email to 279 employees in the Bahraini governmental sector. The findings of the study revealed that occupants in the Bahraini governmental buildings are not strongly satisfied with IEQ factors, especially with sound privacy, followed by visual privacy and amount of space, and then noise levels. The findings also showed that for most IEQ factors, men are more satisfied than women are, those who work in enclosed private offices are more satisfied than those who work in open-plan offices, and those who have central air-conditioning at their workplace are more than those who have a wall-mounted air conditioner. The impact of age, nature of work, duration of working in the current building and at the current workstation, weekly working hours, and proximity to the window were also investigated. Accordingly, a group of recommendations was suggested aiming to improve the levels of occupants’ satisfaction.

Indoor environmental quality (IEQ) factors usually considered in engineering studies, i.e., thermal, acoustical, visual comfort and indoor air quality are individually associated with the occupant satisfaction level on the basis of well-established relationships. On the other hand, the full understanding of how single IEQ factors contribute and interact to determine the overall occupant satisfaction (global comfort) is currently an open field of research. The lack of a shared approach in treating the subject depends on many aspects: absence of established protocols for the collection of subjective and objective measurements, the amount of variables to consider and in general the complexity of the technical issues involved. This case study is aimed to perform a comparison between some of the models available, studying the results of a survey conducted with objective and subjective method on a classroom within University of Roma TRE premises. Different models are fitted on the same measured values, allowing comparison between different weighting schemes between IEQ categories obtained with different methods. The critical issues, like differences in the weighting scheme obtained with different IEQ models and the variability of the weighting scheme with respect to the time of exposure of the users in the building, identified during this small scale comfort assessment study, provide the basis for a survey activity on a larger scale, basis for the development of an improved IEQ assessment method.

Office spaces are often examined using comfort-based measures. Another view is the need-supply fit, which emphasizes the fit of the space for different activities. Here the influence of office types and satisfaction with indoor environmental quality (IEQ) factors on different activities' perceived fit was examined with a large global dataset consisting of 82 315 respondents. The office types included private offices, assigned workstations in shared offices, assigned workstations in open-plan offices, team tables, and flex offices. The IEQ factors were estimations of satisfaction with thermal conditions, noise, air quality, natural light, and office lighting. The perceived fit was the estimation of workplaces’ support for different office tasks classified into eight activity types. The largest proportion of respondents were dissatisfied with thermal conditions (30.7%) and noise (27.9%). However, only dissatisfaction with noise was strongly related to the perceived fit and explained alone 17% of perceived fit for concentrated work. All office types supported office activities well. Satisfaction with IEQ factors explained the perceived fit better than the office types. Satisfaction with IEQ factors alone explained 16−24% of the perceived fit depending on the activity type. Private offices were considered the best fit, especially for concentrated and confidential work as well as remote contacts. The study shows that the need-supply fit approach offers a slightly different perspective on office functioning than comfort-based approaches. Satisfaction with IEQ factors is crucial for functioning in an office. Special care should be paid to noise control especially with activities needing concentration, confidentiality, or special material.

Human cognitive performance is influenced by external factors, including indoor environmental quality (IEQ). Understanding how these factors affect stress, attention, and relaxation is essential in environments such as workplaces and educational institutions, where cognitive function directly impacts performance. This study examines the effects of IEQ on students’ attention and relaxation levels during various lecture periods, focusing on design major students. Three key IEQ parameters (air temperature, relative humidity, and natural lighting) were evaluated for their effects on cognitive states using electroencephalogram (EEG) measurements in a controlled setting. Participants wore non-invasive, portable EEG devices to monitor neurophysiological activity across two sessions, each involving four scenarios: (i) baseline, (ii) increased natural light exposure, (iii) elevated relative humidity, and (iv) increased air temperature. EEG-derived metrics of attention and relaxation were analyzed alongside environmental data, including temperature, humidity, lighting conditions, carbon dioxide (CO2) concentration, total volatile organic compounds (TVOC), and particulate matter (PM), to identify potential correlations. Results showed that natural light exposure improved relaxation but reduced attention, suggesting a restorative effect on stress that may also introduce distractions. Attention peaked under moderately warm, dry conditions (25–26 °C and 16–19% relative humidity), correlating positively with temperature (Pearson correlation coefficient, r = 0.32) and negatively with humidity (r = −0.50). Conversely, relaxation was highest under cooler, more humid conditions (23–24 °C and 24–26% relative humidity). Attention was negatively correlated with CO2 (r = −0.47) and PM2.5 (r = −0.46), suggesting that poor air quality impairs alertness. Relaxation showed weaker but positive correlations with PM2.5 (r = 0.38), PM1.0 (r = 0.35), and CO2 (r = 0.32). Ultrafine particles (PM0.3, PM0.5) and TVOC had minimal association with cognitive states. Overall, this study underscores the importance of optimizing indoor environments in educational settings to enhance academic performance and supports the development of evidence-based design standards to foster healthy, effective learning environments.

Occupant productivity and office indoor environment quality: A review of the literature

This study aimed to examine the real-time indoor environmental quality (IEQ) factors in an office space environment with a dedicated underfloor air conditioning system. Nevertheless, underfloor air distribution (UFAD) system buildings in India do not have reliable studies to record the impact of occupant perception and IEQ factors. This study was conducted in the UFAD office building during the peak monsoon period of 16th – 25th October 2019 in a warm and humid climate region of Mumbai, India. IEQ factors of indoor thermal, air quality, lighting, and noise comfort were examined using an occupant questionnaire survey for sensation, preference and overall acceptability, as well as physical measurements. Furthermore, energy consumption and energy utilization coefficient were determined at different room set-point temperatures. Four hundred and thirty-five responses were collected during the field study. The comfort zone temperature was obtained between 22.24–25.3 °C with near-zero (±0.5) tolerance range. Moreover, 80-95% of the occupants felt comfortable and acceptable within the thermal environment of the room set-point at 22-25 °C. Results showed that the real-time IEQ score was perceived between 0.663-0.846. The real-time IEQ score can be used as a building management strategy that simultaneously improves thermal comfort and indoor air quality.

Individually controlled noise reducing devices to improve IEQ in classrooms of primary schools

Analyzing the impact of indoor environmental quality on physiological responses and work performance: Implications for IEQ control strategies