The benefits of having a high indoor environmental quality (IEQ) for a healthy life and optimal performance are well known. In addition, research has been executed on the effects of indoor environmental parameters such as (day)light, sound/ acoustics, temperature, and air quality on people living with dementia.
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In this article a generic fault detection and diagnosis (FDD) method for demand controlled ventilation (DCV) systems is presented. By automated fault detection both indoor air quality (IAQ) and energy performance are strongly increased. This method is derived from a reference architecture based on a network with 3 generic types of faults (component, control and model faults) and 4 generic types of symptoms (balance, energy performance, operational state and additional symptoms). This 4S3F architecture, originally set up for energy performance diagnosis of thermal energy plants is applied on the control of IAQ by variable air volume (VAV) systems. The proposed method, using diagnosis Bayesian networks (DBNs), overcomes problems encountered in current FDD methods for VAV systems, problems which inhibits in practice their wide application. Unambiguous fault diagnosis stays difficult, most methods are very system specific, and finally, methods are implemented at a very late stage, while an implementation during the design of the HVAC system and its control is needed. The IAQ 4S3F method, which solves these problems, is demonstrated for a common VAV system with demand controlled ventilation in an office with the use of a whole year hourly historic Building Management System (BMS) data and showed it applicability successfully. Next to this, the influence of prior and conditional probabilities on the diagnosis is studied. Link to the formal publication via its DOI https://doi.org/10.1016/j.buildenv.2019.106632
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Not much is known about the favourable indoor air quality in long term care facilities (LTCFs), where older adults suffering from dementia live. Older adults, especially those who suffer from dementia, are more sensible to the indoor environment. However, no special requirements for the indoor air in long term care facilities exist. Due to the decrease in cognition function, it is hard to evaluate comfort and health in this group. Nevertheless, infectious diseases are a persistent problem. Based on literature an assessment methodology has been developed to analyse LTCFs to determine if differences in building characteristics and Heating, Ventilation and Air Conditioning (HVAC) systems influence the spread of airborne infectious diseases. The developed methodology is applied in seven long term care facilities in the Netherlands. After that, the methodology has been evaluated and its feasibility and applicability are discussed. From this study, it can be concluded that this method has potential to evaluate, compare LTCFs, and develop design guidelines for these buildings. However, some adjustments to the methodology are necessary to achieve this objective. Therefore, the relation between the indoor environment and infection risk is not yet analysed, but a consistent procedure to analyse this link is provided.
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Teachers and students need good learning environments to perform well. In this study it is pre-supposed that the spatial properties of classrooms can contribute to the quality of the educational process. Thermal, acoustic and visual conditions and indoor air quality (IAQ) may be extremely powerful in order to support the in-class tasks of teachers and students. But what are the optimal conditions? And do schools provide optimal indoor 2019 ISES ISIAQ Joint Annual Meeting – Abstracts | 362 environmental conditions? Research shows that adequate ventilation and thermal comfort in classrooms could improve academic performance of students. However, different studies also suggest that poor indoor environmental quality in classrooms are common and, in some cases, even unhealthy. This study investigates the relationship between indoor air quality (IAQ), perceived indoor air quality (PIAQ) and building-related symptomsof students in university classrooms via subjective assessment and objective measurement. This study was carried out in 59 classrooms of a university of applied sciences in the northern part of the Netherlands during heatingseason. Responses from 366 students were obtained through a questionnaire. Results shows that carbon dioxide concentrations (CO2) exceed minimum Dutch guidelines in 36% of the observed classrooms. Moreover, after a 40 minute class this raised to 45% of the observed classes. Poor IAQ can affect teachers and students level of attention, cause arousal and increase the prevalence of building-related symptoms. A significant correlation was found between CO2 concentrations and PIAQ and between PIAQ and the ability to concentrate, tiredness and dry skin. The research findings imply that increased CO2 concentrations will affect the PIAQ of students and may cause inability to concentrate, increased tiredness and dry skin. These building-related symptoms can cause distraction and affect the academic performance of students negatively. It is highly recommended to improve IAQ in classrooms by offering better indoor environmental conditions through reducing CO2 concentrations.
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This study explores if multiple alterations of the classrooms' indoor environmental conditions, which lead to environmental conditions meeting quality class A of Dutch guidelines, result in a positive effect on students' perceptions and performance. A field study, with a between-group experimental design, was conducted during the academic course in 2020–2021. First, the reverberation time (RT) was lowered in the intervention condition to 0.4 s (control condition 0.6 s). Next, the horizontal illuminance (HI) level was raised in the intervention condition to 750 lx (control condition 500 lx). Finally, the indoor air quality (IAQ) in both conditions was improved by increasing the ventilation rate, resulting in a reduction of carbon dioxide concentrations, as a proxy for IAQ, from ~1100 to <800 ppm. During seven campaigns, students' perceptions of indoor environmental quality, health, emotional status, cognitive performance, and quality of learning were measured at the end of each lecture using questionnaires. Furthermore, students' objective cognitive responses were measured with psychometric tests of neurobehavioural functions. Students' short-term academic performance was evaluated with a content-related test. From 201 students, 527 responses were collected. The results showed that the reduction of the RT positively influenced students' perceived cognitive performance. A reduced RT in combination with raised HI improved students' perceptions of the lighting environment, internal responses, and quality of learning. However, this experimental condition negatively influenced students' ability to solve problems, while students' content-related test scores were not influenced. This shows that although quality class A conditions for RT and HI improved students' perceptions, it did not influence their short-term academic performance. Furthermore, the benefits of reduced RT in combination with raised HI were not observed in improved IAQ conditions. Whether the sequential order of the experimental conditions is relevant in inducing these effects and/or whether improving two parameters is already beneficial, is unknown.
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Background and aim – In this study, it is pre-supposed that the indoor environmental conditions of classrooms can contribute to the quality of the educational process. Thermal, acoustic and visual conditions and indoor air quality (IAQ) may be extremely supportive in order to support the in-class tasks of teachers and students. This study explores the influence of these conditions on the perceived comfort and quality of learning of students in higher education. Methodology – In a case study design, the actual IEQ of 34 classrooms which are spread over four school buildings in North Netherlands and 276 related student perceptions were collected. The measurements consisted of in situ physical measurements. At the same moment the perceived indoor environmental quality (PIEQ) and the perceived quality of learning (PQL) of students were measured with a questionnaire. Results – Observed are high carbon dioxide concentrations and high background noise levels. A relation was observed between perceived acoustic and visual conditions, IAQ, and the PQL indicating that a poor IEQ affects the PQL. A linear regression analyses showed that in this study the perceived impact on the quality of learning was mainly caused by perceived acoustic comfort. Originality – With the applied innovative measuring instrument it is possible to measure both the actual IEQ as well as the PIEQ and PQL. This method can also be used to assess a reference and intervention condition. Practical or social implications – The applied measuring instrument provides school management with information about the effectiveness of improved IEQ and students’ satisfaction, which can be the basis for further improvement.
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This study examines the impact of moderate and high lighting and indoor air quality (IAQ) conditions on students’ well-being during a regular academic course in higher education. To determine the precise contribution of these two indoor environmental factors, students’ perceptions of their well-being were examined with the Positive and Negative Affect, Basic Emotional Process, and Karolinska Sleepiness Scale. Data were collected from 83 students, resulting in 285 responses, distributed across four combinations of moderate and high IAQ conditions, resp. > 800 ppm ≤ 950 ppm carbon dioxide (CO2) and < 800 ppm CO2, and moderate and high horizontal illuminance (HI) levels, resp. 500 lx and 750 lx. The results indicated that high HI levels did not enhance students’ perceived well-being compared to moderate levels. However, high IAQ conditions significantly contributes to students’ well-being, compared to moderate conditions. Interaction effects between the two factors were observed at moderate conditions.
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Backgroundand aim – In this study, it is pre-supposed that the indoor environmental conditions of classrooms can contribute to the quality of the educational process. Thermal, acoustic and visual conditions and indoor air quality (IAQ) may be extremely supportive in order to support the in-class tasks of teachers and students. This study explores the influence of these conditions on the perceived comfort and quality of learning of students in higher education.Methodology– In a case study design, the actual IEQ of 34 classrooms which are spread over four school buildings in North Netherlands and 276 related student perceptions were collected. The measurements consisted of in situ physical measurements. At the same moment the perceived indoor environmental quality(PIEQ) and the perceived quality of learning (PQL) of students were measured with a questionnaire.Results – Observedare high carbon dioxide concentrations and high background noise levels. Arelation was observed between perceived acoustic and visual conditions, IAQ,and the PQL indicating that a poor IEQ affects the PQL. A linear regressionanalyses showed that in this study the perceived impact on the quality oflearning was mainly caused by perceived acoustic comfort.Originality– With the applied innovative measuring instrument it is possible to measure both the actual IEQ as well as the PIEQ and PQL. This method can alsobe used to assess a reference and intervention condition.Practical or social implications – The applied measuring instrument provides schoolmanagement with information about the effectiveness of improved IEQ and students’ satisfaction, which can be the basis for further improvement.Type ofpaper – Research paper.
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The indoor air quality (IAQ) in classrooms in higher education can influence in-class activities positively. In this context, the actual IAQ and students' perceived IAQ (PIAQ), perceived cognitive performance (PCP), and short-term academic performance (SAP) were examined in two identical classrooms during regular academic courses. During the lecture, key performance indicators (KPI) for the IAQ, i.e. carbon dioxide concentration, particulate matter 2.5, and total volatile organic compounds, were measured. After the lecture, responses of 163 students were collected with a validated self-composed questionnaire and a cognitive test, which covered topics discussed during the lecture. A significant association between the IAQ KPI and the PIAQ was found (p < .000). The PIAQ significantly predicted the PCP (p < .05) and the PCP significantly predicted the SAP score (p < .01). These results indicate that the IAQ in classrooms is associated with the PIAQ and PCP, and therefore is associated with students' SAP.
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Purpose: This field study analyses the quality of the actual thermal comfort and indoor air quality in Dutch office buildings. A linear regression analysis was used to determine how much these variables and demographic variables influenced the perceived thermal comfort of office workers.Approach: Data were collected on-spot at two Dutch office buildings (n=182) during the winter of 2015 and showed that the indoor air in these offices is of good quality and did not affect the perceived thermal comfort significantly. The indoor temperature was the most important variable that influenced the perceived thermal comfort. Indoor temperatures ranged in this study from 18 till 24oC and were therefore at the edge of acceptable European and Dutch standards NPR-CR 1752 (1999), NEN-EN 15251(2007) and NEN-EN-ISO 7730 (2007).Findings: Office workers which experienced a indoor temperature of 20oC graded this temperature the highest (6.7 on a scale from 1-10). At 20oC the percentage of workers that was dissatisfied was the lowest (30%). This study also showed that female workers were more likely to have the sensation that is was too cold than male workers. European and Dutch standards prescribe that an indoor temperature between 21 and 23oC should be the most ideal temperature during wintertime. This study indicates that an indoor temperature higher than 22oC might be too warm for office workers in The Netherlands during wintertime and that application might influence office workers’ satisfaction negatively.
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