A previous study clustered home occupants into archetypes with a questionnaire. This study uses qualitative methods to strengthen those previously-found archetypes with data pertaining to the participants’ home experiences. Focus groups were carried out where generative activities were conducted involving the generation of collages. The first activity dealt with the expression of ‘meaning of energy use at home’ and the second one with the ‘ideal home experience’. Analyses were done with content and thematic analysis. Codes were drawn from the data and were assimilated through an affinity diagram. The diagram produced two categories: building themes and human themes, along with five sub-categories (home, financial, energy, psychological, and behavioural aspects). The outcome shows that each archetype expresses needs and meanings of an ideal home experience and energy use differently from each other. The results provide evidence that generative techniques can be used in energy research. In this case, to validate and substantiate the quantitative archetypes previously produced with a questionnaire. Interpretive knowledge in energy research allows for a better understanding of occupants’ differing behavioural patterns in regards to energy use and comfort. It allows customizing interventions to the archetypes’ specific needs to decrease energy consumption while maintaining comfort.@en

To study the combined effect of different environmental factors on children in a classroom setting, 250 children from seven primary schools were exposed to 36 different environmental configurations (‘all’ and ‘fewer’ acoustical panels; ‘displacement’ and ‘mixing’ ventilation; sound type: ‘children talk’, ‘traffic’, and ‘none’; and ‘direct’, ‘indirect’ and ‘soft’ lighting). In a four-way factorial design, they assessed with 18 groups on eight different days temperature, draught, noise, light and smell. Correlation, three-way ANOVA, comparison tests and multi-regression analysis were used to analyse relationships, and main, cross-modal and interaction effects. The results show that more acoustical panels had a positive effect on the children’s assessment of sound. Sound type had a main effect on the assessment of sound. Statistical significant cross-modal effects were found for lighting and sound type on the assessment of smell. Significant three-way interactions between ‘Vent’, ‘Sound’, and ‘Light’ types were found for smell and light in the ‘fewer panels’ situations; and for light in the ‘all panels’ situations. Multiple-regression analysis also showed that perception of smell was significantly related with draught, sound and light perception in ‘fewer panels’ conditions. Further studies on these cross-modal interactions are recommended, specifically at individual level.@en

Because of COVID-19, the indoor environmental quality (IEQ) in sports facilities has been a concern to environmental health practitioners. To develop an overall understanding of the available guidelines and standards and studies performed on IEQ in sports facilities, an extensive literature study was conducted, with the aim of identifying: (1) indicators that are being used to assess IEQ in different sports facilities; (2) indicators that are potentially interesting to be used to assess indoor air, in particular; (3) gaps in knowledge to determine whether sports facilities are safe, healthy and comfortable for people to stay and perform their activities. The outcome indicates that most current standards and previous investigations on IEQ in sports facilities mainly focused on dose-related indicators (such as ventilation rate), while building-related indicators (such as ventilation regime) and occupant-related indicators (such as IEQ preferences) were rarely considered. Little attention is given to the fact that ventilation systems may play an important role in the air quality of the location, and few investigations have been performed on the transmission of SARS-CoV-2. This study recommends more research into both occupant and building-related indicators as well as cross-modal effects between various IEQ factors for developing future standards on sports facilities.@en

Sounds (e.g., human activity, nature, building systems) are one of the indoor environmental stimuli that may have positive and/or negative effects on students’ well-being and performance in educational buildings. Students in educational buildings have individual acoustical preferences and needs as portrayed by occupant-related indicators, for example perception. Acoustical guidelines for educational buildings are generally focused on acoustical performance in terms of dose-related (e.g., sound pressure level) and building-related indicators (e.g., sound absorbing walls), while occupant-related indicators (e.g., heart rate) are rarely mentioned. In contrast, previous studies such as indoor soundscape studies, do take into consideration occupant-related indicators, including physiological and psychological. Therefore, this study aimed at summarizing these indicators in a comprehensive overview that is essential for investigating the students’ acoustical preferences and needs in educational buildings. A literature review of relevant studies in the domain of indoor acoustics and soundscape was carried out. A number of key indicators (occupant-related, dose-related, building-related) and methods that are fundamental to be considered were identified. Only in a few studies, students’ acoustical preferences and needs were investigated by considering occupant-related indicators (both physiological and psychological). In addition, dose-related indicators of other indoor environmental quality (IEQ) factors and building-related indicators were rarely taken into account in previous studies.@en

There are indications that energy-retrofitted buildings can create risks for indoor environmental quality (IEQ) and therefore for health and comfort of occupants. A review was conducted to identify and verify those risks, within three themes: building envelope, heating, ventilating and air conditioning (HVAC)-systems, and occupants. Publications from the last five years in major peer-reviewed journals from different fields (energy, buildings, indoor air, social sciences) were found by using a variety of keywords (health effects, occupant behaviours, energy-efficient retrofitting, etc.). For the building envelope, retrofitted buildings tend to be air-tighter and more thermally insulated. Hence, humidity problems, build-up of pollutants, and overheating may occur. Installing HVAC-systems and issues within (ducts, filters, maintenance, noise) may also compromise IEQ. Although relationships are difficult to establish, evidence shows that certain retrofits increase the risk of health problems, particularly for airways, skin, and eyes. Despite the installation of energy-retrofitting technologies, not all buildings lower their energy consumption. This is partly due to occupants (behaviours, preferences, needs, awareness) and partly due to technical issues. The studies reviewed, mainly focused on the performance gaps of energy-retrofitted homes and on energy-saving measures. “Comfort” and “health” tend to be disregarded, with both being seldom measured and only assessed by simulation. Occupant behaviours, preferences, and needs are understudied and need to be incorporated into the research and development of retrofitting measures. More interdisciplinary approaches are needed, in which buildings & HVAC-systems, occupants, health and comfort, and IEQ are investigated as interacting elements and based on an integrated approach.@en

To identify current problems in the classroom and to conceptualize design solutions by primary school children to solve these problems, 335 children from seven primary schools participated in a workshop held in the Experience room of the SenseLab, comprising of two parts. In part 1, the children were asked to think about their own classroom at school and to choose an IEQ-problem in their own classroom that they are bothered with. In part 2 of the workshop, the children were asked to imagine they are an inventor or scientist in 2040 with all resources available and to make a design for the future. The content analysis of the problems and solutions appearing in the drawings and the written text resulted in 5 themes (light, noise, temperature, air and other than IEQ) and 16 sub-themes (11 for the problems and 5 for the solutions). Noise-related problems were most frequently reported (58%), followed by temperature (53%), air (22%), and light (16%). Girls reported more problems than boys, which is possibly related to a better recollection of negative feelings towards those problems in their classrooms. 47% of the children proposed solutions related to more than one IEQ-problem. Solutions ranged from existing solutions, for example headphones to protect against noise to far-fetched solutions such as send noisy children away by means of a rocket. The outcome showed that children can be valuable contributors in co-designing ‘new’ or ‘adapted’ classroom environments.@en

There is a need for reducing dwellings’ energy consumption while maintaining a comfortable and healthy indoor environment. This review was performed to provide a steppingstone for identifying new methods for studying everyday home energy use and comfort. First, an overview of comfort is given as seen from different disciplines, depicting the subjective and multidimensional nature of comfort. This is followed by the biological component of comfort, reflected as an emotional, behavioural, and physiological reaction to environmental stimuli. Subsequently, links between comfort, health, and wellbeing are introduced. The second part of the review focuses on energy and buildings, with the connection between energy and behaviours-detailing possible explanations of performance gaps, and the pathways from energy to health. To conclude, human sensation of comfort is more complex than the perception of thermal, acoustical, visual stimuli, or air quality environment. Comfort is a reaction to the environment that is strongly influenced by cognitive and behavioural processes. Habits and controllability have been identified as paramount in the links between comfort and energy consumption. In this holistic view of comfort linked to health, comfort is referred to as ‘wellbeing’. The first steps for new directions of the study of comfort and energy are presented.@en

Background: This paper demonstrates the effectiveness of the TwoStep cluster analysis and the development and first results of a new questionnaire for measuring comfort, health, and energy habits. The justification for the questionnaire is to consolidate into one instrument questions of six specific domains about occupants’ energy consumption patterns, from the behavioural and psychological perspectives. Methods: The questionnaire was developed from a literature review, iterative conceptualization, and testing. The resulting instrument was administered to a sample of home occupants, comprising of bachelor students of Architecture of the Delft University of Technology. The objective of the study was to examine the effectiveness of the TwoStep cluster analysis to produce occupant profiles. 316 emails were sent out inviting participants to complete the questionnaire. Results: With the TwoStep cluster analysis, it was possible to distinguish six different archetypes of occupants based on their behavioural characteristics. These were the Relaxed Optimists, Unconcerned Indifferents, Restrained Sensitives, Positive Absolutists, Incautious Negativistics, and Resigned Savers. Conclusion: The results provide promising evidence of the questionnaire's potential to distinguish different occupant energy consumption profiles based on distinct psychosocial domains in a single and concise instrument, while also showing that the analysis method is appropriate for the type of variables gathered. The value of recognizing these profiles allows for a better understanding of occupants’ differing energy consumption patterns in their homes and tailoring interventions to their specific needs.@en

To better understand home energy consumption, it is important to study the behaviours of occupants in their homes, especially in relation to their comfort needs. A mixed methods study comprising of a questionnaire, interviews, indoor environmental parameters monitoring, and energy consumption readings was performed to group home occupants based on their behavioural patterns. The TwoStep cluster analysis produced five clusters of home occupant with the data from 761 questionnaire respondents. The clustering model comprised of 28 variables including constructs of emotions, comfort affordances, and locus of control. Then, in-depth semi-structured interviews were conducted and IEQ monitoring and energy readings were taken with 15 of the questionnaire respondents. The results of the field study were used to substantiate the findings of the questionnaire. The combination of the statistical clusters with the data from the field study resulted in five archetypes: five distinct types of home occupants, differing in their behavioural motivations towards achieving comfort, and their use of energy when doing so. This study shows that a mixed methods approach is valuable for better understanding energy consumption and implementing archetype-customized lines of action to reduce energy use and maintain comfort.@en

This research is aimed at better understanding how occupants use energy in their homes from a comfort-driven perspective, in order to propose customized environmental characteristics that could improve the occupants’ comfort while reducing energy consumption.@en

Building retrofitted to be resilient in the face of future climates may present risks for the health and comfort of the occupants, due to the indoor environmental quality changes involved under current building practices. This chapter is a literature review of recent peer-reviewed papers from a variety of fields identifying such potential hazards. Three topics are investigated: building envelope, HVAC systems and occupants. In terms of the building envelope, resilient buildings currently lead to more airtightness and thermal insulation, which can create humidity problems, accumulation of air pollutants or overheating. HVAC systems, however efficient, can jeopardize the indoor environmental quality, through ducts, filters, noise and maintenance. Respiratory system, eyes and skin conditions can arise with certain retrofitting measures. Moreover, such measures do not necessarily lead to energy savings, partly due to the occupants and their behaviours and partly due to the technologies and their feedback. Human factors should be combined into the development of retrofitting technologies. Thus, interdisciplinarity is needed to develop resilient buildings that will be energy-efficient and also healthy and comfortable for their occupants and the technologies need to be researched as interdependent components to be synthesized in their performance to result in a single enhanced goal.@en

Het onderhavig onderzoek was gericht op het vinden van relaties tussen eigenschappen van de woonomgeving en rhinitis (irritatie van het slijmweefsel in de neus) bij studenten. Een vragenlijst werd verspreid onder vier groepen van studenten van drie technische universiteiten in Nederland. Zelf-gerapporteerde eigenschappen van 396 studenten en hun woningen, werden gelinkt met zelfgerapporteerde rhinitis. De resultaten laten zien dat biologische verontreinigingen (veroorzaakt door huisdieren), chemische verontreinigingen (veroorzaakt door MDF in de slaapkamer), ventilatie (openen van raam in slaapkamer) en fysieke activiteit (training), geassocieerd waren met rhinitis bij de studenten. Verder onderzoek is nodig naar de onderliggende oorzaken om rhinitis bij jonge volwassenen te voorkomen.@en

Het onderhavig onderzoek was gericht op het vinden van relaties tussen eigenschappen van de woonomgeving en rhinitis (irritatie van het slijmweefsel in de neus) bij studenten. Een vragenlijst werd verspreid onder vier groepen van studenten van drie technische universiteiten in Nederland. Zelf-gerapporteerde eigenschappen van 396 studenten en hun woningen, werden gelinkt met zelfgerapporteerde rhinitis. De resultaten laten zien dat biologische verontreinigingen (veroorzaakt door huisdieren), chemische verontreinigingen (veroorzaakt door MDF in de slaapkamer), ventilatie (openen van raam in slaapkamer) en fysieke activiteit (training), geassocieerd waren met rhinitis bij de studenten. Verder onderzoek is nodig naar de onderliggende oorzaken om rhinitis bij jonge volwassenen te voorkomen.@en

There is a need for making people aware of the importance of indoor environmental quality for their health and comfort. A simple guide to educate yourself was created, together with a questionnaire to make you aware of your own indoor environment. The questionnaire was distributed among four groups of students from three different universities in The Netherlands. The procedure and the first descriptive results are presented. Further analysis will be performed for educational and scientific purposes.@en

There is a need for making people aware of the importance of indoor environmental quality for their health and comfort. A simple guide to educate yourself was created, together with a questionnaire to make you aware of your own indoor environment. The questionnaire was distributed among four groups of students from three different universities in The Netherlands. The procedure and the first descriptive results are presented. Further analysis will be performed for educational and scientific purposes.@en

Next to personal, psychosocial and physiological aspects, environmental aspects of homes may affect the health and comfort of their occupants. This study aimed to investigate the multifactorial character of both rhinitis and headaches among five groups of students from universities in five different cities: Taichung (Taiwan), Concepcion (Chile), Paramaribo (Suriname), Beijing (China) and Delft (The Netherlands). Among the students studied, 18% declared having suffered from rhinitis in the last 12 months, and 30% from headaches in the last 3 months. Self-reported characteristics of 682 students and their homes were linked to self-reported rhinitis and headaches. Logistic regression modelling was applied to explore relations between building-related factors and rhinitis, and between building-related factors and headaches. After full adjustment, the regression model for both rhinitis and headaches confirmed their multifactorial character. While personal-related factors family rhinitis and age were associated with rhinitis, negative events and PANAS negative were with headaches. Biological pollutants (caused by pets) were associated both with rhinitis and headaches; chemical pollutants, caused by open bookshelves and lack of sweeping floors, were associated with rhinitis. The study concludes that the identified risk factors seemed independent of season or climate region.@en

Background: The initial aim was to study the effects of face masks worn by recently infected individuals on the airborne spread of SARS-CoV-2, but findings motivated us to proceed with comparing the presence of SARS-CoV-2 in air samples near infected individuals at home with those near infected intensive care unit (ICU) patients. Aim: To assess the presence of SARS-CoV-2 in the air of homes of infected individuals and in ICU rooms of critically ill patients with COVID-19 who were undergoing different forms of potential aerosol-generating medical procedures. Methods: A high-volume air sampler method was developed that used a household vacuum cleaner with surgical face masks serving as sample filters. SARS-CoV-2 RNA was harvested from these filters and analysed by polymerase chain reaction. Fog experiments were performed to visualize the airflow around the air sampler. Air samples were acquired in close proximity of infected individuals, with or without wearing face masks, in their homes. Environmental air samples remote from these infected individuals were also obtained, plus samples near patients in the ICU undergoing potential aerosol-generating medical procedures. Findings: Wearing a face mask resulted in a delayed and reduced flow of the fog into the air sampler. Face masks worn by infected individuals were found to contain SARS-CoV-2 RNA in 71% of cases. SARS-CoV-2 was detected in air samples regardless of mask experiments. The proportion of positive air samples was higher in the homes (29/41; 70.7%) than in the ICU (4/17; 23.5%) (P < 0.01). Conclusion: SARS-CoV-2 RNA could be detected in air samples by using a vacuum cleaner based air sampler method. Air samples in the home environment of recently infected individuals contained SARS-CoV-2 RNA nearly three times more frequently by comparison with those obtained in ICU rooms during potential aerosol-generating medical procedures.@en

Since the outbreak of COVID-19, wearing a mask, voluntary or obligatory, has led to diverse and numerous designs. Guidelines for minimum requirements include tests for visual inspection, strength, filtration, and breathing resistance, but not for the fit of a mask. The fit of a mask was assessed by testing the outward leakage of exhaled breath based on the visualization of coloured mist exhaled by a manikin head. Fourteen masks were selected based on differences in design, such as type of material, shape (cheek wings vs. none), filter type, and the number of layers. Leakage expressed in mean mist percentages (visualized with a camera), patterns of coloured mist left inside the masks, as well as visual fit of the masks on the manikin head, showed that a loose fit mask results in more leakage. Also, combining quantitative with qualitative assessment proved to be complementary. Future tests should be conducted on a range of users, covering the best fit over time as well breathability, use, and comfort. The use of face masks, whatever their characteristics, seem an adequate strategy to reduce the dispersion of potential ‘infected’ aerosols into the space from people, as opposed to not wearing one.@en

Recent studies have shown that both personal and building-related factors may affect the health and comfort of occupants in their homes. It is also known that people differ in their needs and can therefore respond differently to these stressors. Therefore, based on the large database from the survey conducted yearly from 2016 to 2020 among the first-year students of the faculty of Architecture and the Built environment at the Delft University of Technology, this study aimed to explore the associations between self-reported rhinitis/stuffy nose/migraine/headache, and the indoor environment of the students' homes, taking into account potential confounders and profiles. Two-steps cluster analysis resulted in three profiles of students based on their IEQ-related perceptions: Cluster 1 with the highest reported percentage of symptoms and the lowest reported percentage of diseases; Cluster 2 with moderate reported symptoms and diseases; and Cluster 3 with the lowest percentage of reported symptoms and the highest percentage of reported diseases. Logistic regression modelling showed that risk factors contributing to having rhinitis, stuffy nose, migraine and/or headache, differ per cluster, and showed little overlap with the all-respondents group. Moreover, when there is an overlap, the associated risk factor might increase the risk for one cluster, while for another it decreases the risk, indicating differences in response between the different clusters; and therefore, the importance of clustering instead of considering all respondents as one.@en