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In recent years, our time spent indoors has risen to around 90% and to maintain an occupant's comfort and well-being, Indoor Environmental Quality (IEQ) is monitored. Concerned with inhabitant's satisfaction and health, the adoption of smart solutions for IEQ monitoring and improvement has expanded. The solution this study explores is an occupant-centric approach involving the implementation of an Internet of Things (IoT) IEQ sensing network in a prominent office skyscraper in Hong Kong. Over the course of 15 months, real-time IEQ data were collected from 12 locations within the building. The data were collected at 1-min time intervals and consisted of readings of indoor air temperature, radiant temperature, relative humidity, air velocity, carbon dioxide (CO2), particulate matter (PM10 and PM2.5), horizontal illuminance levels, and sound pressure levels, which served as the basis of the assessment made about the qualities of thermal comfort, indoor air quality (IAQ), aural comfort, and visual comfort. Compared to traditional periodic surveys, this IoT-based sensing network captured instantaneous environmental variations, providing valuable insights into the indoor environment's spatial characterization and temporal dynamics. This smart solution also assisted facility management in terms of identifying sources of discomfort and developing effective mitigation strategies accordingly. This study presents an occupant-centric approach to improve occupant comfort and energy efficiency within office buildings. By customizing the built environment to enhance occupants' well-being, comfort, and productivity, an emphasis is placed on a more personalized and occupant-focused design strategy. This approach integrates technical design with human experience, highlighting the importance of real-time physical and subjective surveys for achieving optimal results. [ABSTRACT FROM AUTHOR]

There has been an increasing awareness of indoor air quality (IAQ) management in green building designs, driven by the need to mitigate potential health risks and create sustainable and healthy indoor environments. The COVID-19 pandemic has further highlighted the critical role of ventilation and IAQ in reducing the risk of indoor airborne transmission. Governments and organisations worldwide have responded to this growing concern by implementing ventilation requirements and updating IAQ standards and guidelines. In the case of Hong Kong, a developed and densely populated city characterised by high-rise buildings, this study aims to provide a strategic framework for non-governmental agencies to address IAQ issues effectively. A comprehensive review of policies, regulations, and guidelines by international bodies and individual governments, along with an examination of the current IAQ management scheme in Hong Kong, has been conducted. Drawing inspiration from successful IAQ management strategies, the study aims to identify insights and potential pathways for the city's future development of IAQ management strategies. Overall, this research highlights the importance of proactive IAQ management for buildings and offers a roadmap for Hong Kong's pursuit of healthier indoor environments. [ABSTRACT FROM AUTHOR]

Experimental studies can provide understanding, knowledge and real-case empirical evidence on the effects of building ventilation and environmental factors on airborne transmission in hospitals. Information obtained from existing studies gives insight into formulating engineering solutions and management practices to combat nosocomial airborne infections. A systemic review was conducted to summarize the experimental methods, research interests, useful results and limitations. With a steady but slow trend of increasing interest, experimental studies have been focusing mainly on the effects of ventilation systems, strategies and configurations on airborne transmission. The dispersion of bioaerosols under the combined effects of environmental factors, emission scenarios and human movement was investigated. Localized ventilation, air purifiers and disinfection technologies were also examined. The experimental techniques and some useful insights on optimal ventilation strategies and management practices were summarized and highlighted. Limitations of the empirical studies included sampling difficulties, limited scale and a number of testing scenarios, uncontrolled/unconsidered influencing factors and the media for experimentations. Using IoT-based sampling devices for experiments and real-time monitoring of bioaerosols or their surrogates, field surveys on a case-by-case basis in hospitals and interdisciplinary studies and collaborations could help overcome the research challenges and provide practical and effective solutions to minimize airborne transmission in hospitals. [ABSTRACT FROM AUTHOR]

Optimising ventilation strategy for an indoor environment necessitates systematically evaluating the influence of a diverse combination of physical and operational parameters in the design space. This study proposes a methodology that couples an evolutionary algorithm (genetic algorithm) with an evaluation mechanism (computational fluid dynamics) to determine the optimal ventilation strategy for an inpatient ward. The traditional approach would exhaustively simulate numerous scenarios to identify the optimal combination of parameters meeting the design objective. The proposed methodology would iteratively evaluate diverse design solutions with fewer CFD simulations than the traditional approach. The results of design space exploration suggest that design parameters, namely, location of the infected patient; air change rate; flow rate through local exhaust grille; and number, location and size of supply air diffuser and local air exhaust grille, are critical in minimising the risk of cross-infection caused through contact transmission in a ward. [ABSTRACT FROM AUTHOR]

This study investigates window opening and closing behaviors in residential bedrooms in Hong Kong by examining occupants' habits regarding window operation, window opening and closing behavior, and the influence of environmental and contextual factors. Using self-reported survey data on window opening and closing behavior and outdoor environmental data from an open-source database, univariable and multivariable logistic mixed-effect models were developed to evaluate the impact of various parameters. The findings indicate that outdoor environmental factors have a limited influence on window opening and closing probabilities. Conversely, time of the day was identified as a significant factor, emphasizing the role of occupant habits and preferences in determining these probabilities. Importantly, the study results agreed with the observations that the drivers between window opening and window closing differed, further emphasizing the need for separate modeling. The study highlights the importance of considering environmental and contextual factors when predicting window operation behaviors. This study contributes to our understanding of building occupant behavior and provides valuable insights for building designers and engineers to enhance energy simulations and optimize building performance. • The time of the day affects window usage. • Occupant habits and preferences influence window opening and closing behaviors. • Drivers for window opening and closing differ. • Separate modeling is needed for window opening and closing. [ABSTRACT FROM AUTHOR]

An accurate indoor environmental quality (IEQ) model is essential to design and maintain a comfortable indoor environment. Due to the complexity of IEQ modelling and subjective nature of IEQ responses, there is a need to update the subjective–objective relationship of IEQ model when new information is available. In this study, a Bayesian approach for IEQ model updating is proposed to systematically relate new subjective IEQ responses towards the environment to the existing beliefs. With a selected target sample size and an acceptable error, the statistical significance of data is evaluated and incorporated into the updated IEQ model. Bayesian updating framework is able to enhance the accuracy of IEQ prediction and shall be a useful tool for managerial decision-making in maintaining a comfortable indoor environment. [ABSTRACT FROM AUTHOR]

This study investigates the indoor environmental quality (IEQ) responses from occupants living in very small residential units that are unique to Hong Kong. Through the changes in environmental parameters, including thermal, indoor air quality, visual and aural, the study demonstrates that the overall IEQ acceptance in these units is different from the one in general residential building environments. Results show that occupants of these units are more sensitive to warmth and operative temperature change as compared to occupants of general residential buildings. A small variation of thermal acceptance suggests that the small unit occupants have already developed certain degree of tolerance to hot conditions. The adaptation to the reality of a hot environment is also reflected in the overall IEQ acceptance. It is believed that very small space residents have developed tolerance and adaptation to an unchangeable reality, changing environmental conditions does not necessarily alter their acceptance of individual IEQ aspects and overall IEQ. [ABSTRACT FROM AUTHOR]