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Ventilation in European dwellings: A review
Abstract
Adequate ventilation is essential for the health and comfort of building occupants. This review examines, first of all, why residential ventilation is an issue of concern in Europe and how is related to the human health. A review of the current status of residential ventilation standards and regulations in Europe is also provided, as a reference. Finally, a review of measurements of ventilation rates in European dwellings is provided, where the compatibility with the European standards/regulations is examined. The review shows that ventilation is increasingly becoming recognised as an important component of a healthy dwelling. Ventilation requirements receive major attention in building regulations, across Europe. However, ventilation measurements across Europe show that ventilation is in practice often poor, resulting in reduced ventilation rates (lower than 0.5 h−1, which is currently a standard in many European countries), increased concentrations of indoor pollutants and hence exposure to health risk. Surveys showed that although occupants generally think that ventilation is important, their understanding of the ventilation systems in their own houses is low, resulting to under-ventilated homes.
... J o u r n a l P r e -p r o o f Thus, there are previous studies of indoor ventilation [19][20][21][22], some even making comparisons between the minimum regulated ventilation and the real one [23]. ...
... Regarding the countries analysed and the reason why not all countries in the European Union are addressed in this document, it should be noted that it is a representative sample of European countries with different climatology, but whose regulation is more related to ventilation directives, as already indicated in the study carried out by Christine Dimitroulopoulou [22] and which has served as a starting point for this research. ...
... In Europe, the regulation of ventilation in dwellings has been developed in each country following its criteria and, in some cases, certain guidelines of the European Union. Table 2 shows the 2010 regulations [22] and those in force in 2022, relative to the member states that have been the subject of the study. ...
The airborne transmission of SARS-CoV-2, the virus that causes Covid-19 disease, has been recognized as an essential route of contagion, so adequate ventilation is vital indoors. For this reason, the research goal focuses on carrying out the study and evolutionary and comparison analysis of the regulation of ventilation rates in dwellings in Europe (2010–2022) and on determining whether modifications are necessary for the said regulation based on the recommendations of competent international organizations. To do this, the methodology followed initially starts from the study carried out in 2010 by Christine Dimitroulopoulou, in which the existing regulation in various European countries regarding ventilation in dwellings was studied. Once this study has been analysed, it continues to update and compare the regulation of the different European countries cited in the said work, detecting during the process if a modification is necessary based on the recommendations indicated by international organizations such as the WHO or ECDC. The results and conclusions indicate that few countries have significantly changed their ventilation rates. Although the existing ones may be admissible, requiring controlled ventilation in the different regulations would be convenient.
... volatile and semivolatile organic compounds, cleaning chemical agents, traffic related pollutants, environmental tobacco smoke) and biological (e.g. molds, virus, spores, cells, fragments, and bacteria) agents [146,147]. Low ventilation rates affect also the human productivity and comfort perceptions [146,147]. Similarly, they favor the concentration of chemical and biological pollution and dust [146,147] that may damage heritage artifacts, collections, archives, and building surfaces [148,149]. ...
... molds, virus, spores, cells, fragments, and bacteria) agents [146,147]. Low ventilation rates affect also the human productivity and comfort perceptions [146,147]. Similarly, they favor the concentration of chemical and biological pollution and dust [146,147] that may damage heritage artifacts, collections, archives, and building surfaces [148,149]. A balance between ventilation requirements for human comfort, IAQ, pollution concentration, heritage conservation, and energy savings is needed especially in historic buildings [147]. ...
... Low ventilation rates affect also the human productivity and comfort perceptions [146,147]. Similarly, they favor the concentration of chemical and biological pollution and dust [146,147] that may damage heritage artifacts, collections, archives, and building surfaces [148,149]. A balance between ventilation requirements for human comfort, IAQ, pollution concentration, heritage conservation, and energy savings is needed especially in historic buildings [147]. ...
It is estimated that EU cultural heritage (CH) buildings represent 30% of the total existing stock. Nevertheless, all actions in terms of refurbishment need a deep knowledge based on the diagnosis of the built quality. For this reason, the paper aims to provide a comprehensive review about the applicability of non-destructive techniques (NDT) and advanced modelling technologies for the diagnosis of heritage buildings. Considering a time span of two decades (2001-2021), a bibliometric analysis was performed, using data statistics and science mapping. Subsequently, the most relevant studies on this topic were evaluated for each technique. The main findings revealed that: (i) most of studies were conducted on Southern European countries; (ii) 36% of publications were journal papers and only 2% corresponded to reviews; (iii) “photogrammetry” and “laser applications” were identified as consolidated techniques for historic preservation, but they are only linked with HBIM and deep learning; (iv) a significant gap on quantitative NDT was detected and consequently, future researches should be performed to propose a common diagnosis protocol; (v) artificial neural networks have several barriers (i.e. data privacy, network security and quality of datasets). Hence, a holistic approach should be adopted by the European countries.
... Natural ventilation is a dominant type of ventilation system in European households [1]. In Polish dwellings, a passive stack ventilation is the mostly applied natural ventilation system. ...
... Insufficient ventilation in naturally ventilated buildings results in the increased concentration of indoor air pollutions and poor indoor air quality [2]. Low ventilation influences people's health and well-being, has an influence on sleep quality and on the nextday performance [1][2][3][4]. Poor ventilation is commonly recognised as one of the reasons of the increased rate of allergy, asthma and other respiratory illness among the inhabitants [3]. Children, in particular, are prone to such illnesses. ...
The role of interzonal airflows is especially pronounced in naturally ventilated buildings. In such buildings, reversed airflows in the ventilation stacks might occur as well. This affects the air exchange rate and contaminant distribution in buildings. A significant increase in carbon dioxide concentration is a characteristic phenomenon for poorly ventilated rooms. This paper demonstrates the application of metabolic carbon dioxide concentration measurements for interzonal airflow estimation in naturally ventilated buildings. The presented method is based on the continuous measurements of CO2 concentration at one point in each zone. These measurements are used to estimate airflow pattern in a multizone building by applying an inverse analysis. The developed methodology employs an iterative Levenberg-Marquardt procedure to maximise the nonlinear likelihood function. The validity of the method was verified against measurements carried out in a single naturally ventilated room. Further, the method was applied to calculate the airflow pattern in two apartments in Poland, containing 4 and 6 zones. The obtained results revealed very poor ventilation in both investigated apartments and reversed airflow in exhaust ducts. The amount of fresh air entering the rooms was insufficient to ensure good indoor air quality. The developed methodology can be effectively used as a diagnostic tool to identify the potential problems with ventilation systems.
... Lastly, in cluster 3 (blue color), there are 6 terms that show a strong link of 'ventilation' with 'indoor air' and 'air quality'. It is known that adequate ventilation is essential for the health and comfort of building occupants, and the choice of ventilation system ultimately depends on indoor air quality requirements, heating and cooling loads, and also outdoor climate [44]. Thus, it is interesting to provide clarification on how comfort temperature is related to indoor and outdoor temperatures. ...
... It was found that when the outdoor air temperature was low, the indoor air temperature distribution fell into two groups, where the indoor temperature for one of the dwellings was higher than the other dwelling [23]. ing and cooling loads, and also outdoor climate [44]. Thus, it is interesting to provide clarification on how comfort temperature is related to indoor and outdoor temperatures. ...
Residential buildings instigate a vital role in creating a safe and comfortable indoor living environment. The phenomenon of overheating, an impact of climate change, can cause a negative effect on residents’ productiveness and heat-related illnesses and can even force high pressure on electricity generation by increasing the risk of power outages due to excessive peak cooling and heating requirements. Various issues on building thermal comfort are being evolved and discussed in review articles. However, there are few articles that review the current condition of adaptive thermal comfort studies and the potential for energy savings in residential buildings. Therefore, the aims for this paper are to: identify comfort temperature ranges in residential buildings, investigate the correlation of comfort temperature with indoor and outdoor temperatures with the aid of ‘comfort threads’, and clarify the effect of adaptive measures on residential energy saving potential. This study obtained a large variation of residential comfort temperatures, which mostly depend on the climate and operation modes of the building. ‘Comfort threads’ explains that people are adapting to a large variation of indoor and outdoor temperatures and the wide range of comfort temperature could provide significant energy savings in residential buildings. This review provides insight on and an overview of thermal comfort field studies in residential buildings.
... The results of a review of national requirements and practitioner guidelines in seven European countries are presented in the second chapter of this report. They are in line with earlier reviews by Dimitroulopoulou (2012) and Chenari et al. (2016). Dimitroulopoulou (2012) points out that ventilation is perceived as an important component of a healthy dwelling and that ventilation requirements receive significant attention in European building regulations. ...
... They are in line with earlier reviews by Dimitroulopoulou (2012) and Chenari et al. (2016). Dimitroulopoulou (2012) points out that ventilation is perceived as an important component of a healthy dwelling and that ventilation requirements receive significant attention in European building regulations. Additionally, the results of the present review show that mechanical ventilation systems seem to be already dominant in newly built low-energy residential buildings. ...
The objective of Subtask 4 in the IEA EBC Annec 68 was to integrate knowledge and results from remaining Subtasks and present them in the context with current knowledge. The focus of the Subtask 4 was on practitioners dealing with ensuring high Indoor Air Quality (IAQ) in modern low-energy residences, the demands and challenges they meet during daily work. This especially includes architects and ventilation designers, facility managers, property developers and employees of public authorities. This publication is a result if Subtask 4’s work. It brings a collection of 24 “case studies” related to IAQ design and control in Low-Energy Residential Buildings. By a “case study” we mean a real life construction project, laboratory investigation or a simulation study that provides innovative approach. The case studies were selected to give the practitioners new insigts, inspiration and motivation to go along new paths leading to sustainable and comfortable homes of the future. The report is organized into three main chapters: “Ways to design residential ventilation in the future” and “Towards better performance and user satisfaction”. The descriptions of case studies are accompanied by “lessons learned” sections aiming directly at practical utilization of results as well as recommended future reading section providing the most important references.
... The IoT technology and fuzzy logic control make the system more efficient than the normal system because it can adjust the fan speed based on air pollution [96]. IAQ controlling combined with an indoor air monitoring system can produce a more efficient system [5], [104]. Figure 4.8 shows the implementation of IAQ monitoring and controlling hardware using IoT technology combined with two sensors (CO 2 and PM 10 ) and a fan. ...
... • This IAQ system is incredibly valuable in observing air quality status inside a building to more readily comprehend the present condition of air quality to consider the conduct of environmental conditions [105]. • A ventilation system can optimize air conditions such as IAQ and thermal comfort for individuals living or operating there, considering their health, prosperity and comfort [104]. ...
Internet of Medical Things (IoMT) is attracting a lot of attention from the clinical
scientific community. The medical devices in IoMT collect vital health- related data
over the internet. Patients are given detailed supporting evidence to help them during
recovery. Because of various medical equipment, attackers can change the address
of devices. Certain patients suffering from illnesses like brain tumours are at risk of
dying due to this. Brain tumours are caused by a mass of abnormal cells in the brain,
and they can damage the brain and endanger one’s life. Brain tumour diagnosis, prognosis,
and treatment are all essential. The biopsy and analysis of CT scans or MRIs
that are repetitive, inefficient for vast amounts of data, and enable radiologists to make
assumptions are common techniques for identification. To address these issues, many
software techniques have been proposed. However, there is still a great need to develop
a technology that can identify a brain tumour with high specificity in a short period.
Furthermore, it is critical to select criteria that will allow predictions to attain
exceptional accuracy. The brain is the most affected by tumours that grow irregularly.
Early identification of such cancers greatly aids in the provision of successful
therapy. The first step in diagnosing a brain tumour is to process medical images. It
necessitates various imaging modalities such as computerised CT- Scan, X- ray, and
magnetic resonance imaging (MRI). The primary goal of brain tumour image processing
is to determine the precise size and location of the tumour in the brain. The
precise size and location of the tumour aid in the identification of abnormal growth
in the brain. Detection of brain tumours using MRI is a difficult endeavour even for
highly trained professionals. The MRI image processing software understands how
to process and segment out brain tumours. We split MRI image processing into four
stages: pre- processing, picture segmentation, feature extraction, and image classification.
We used various image segmentation algorithms to separate the brain tumours
like seed region growing, threshold segmentation, watershed, fuzzy c- mean, histogram
threshold etc. We evaluated the accuracy of various approaches and discovered
that the seed region growing method outperformed with 92.5% accuracy.
... On this matter, there is mounting evidence of the importance of increasing outdoor air supply for the achievement of healthy indoor environment. The increase in ventilation rate (i.e. the supply of outdoor air [7]) amplifies the dilution of indoor pollutants, removes excess of CO 2 , and reduces indoor odor and airborne transmission of pathogens, enhancing thereby the IAQ for occupants [8][9][10]. Dal & Zhao [11] showed that the probability of cross-infection in confined spaces decreased as ventilation increased. ...
... Ventilation is recognized as an important factor influencing the transmission of such infectious aerosols [10,[27][28][29]. The purpose of ventilation is the dilution of the entire indoor space (i.e. the macroenvironment): the higher the ventilation rate, the more prominent the dilution effect of indoor pollutants, and the healthier indoor air is for occupants [8]. A study by Dai & Zhao [11] reported that the probability of cross-infection in confined spaces decreased as ventilation increased. ...
Airborne disease transmission in indoor spaces and resulting cross-contamination has been a topic of broad concern for years – especially recently with the outbreak of COVID-19. Global recommendations on this matter consist of increasing the outdoor air supply in the aim of diluting the indoor air. Nonetheless, a paradoxical relationship has risen between increasing amount of outdoor air and its impact on increased energy consumption – especially densely occupied spaces. The paradox is more critical in hot and humid climates, where large amounts of energy are required for the conditioning of the outdoor air. Therefore, many literature studies investigated new strategies for the mitigation of cross-contamination with little-to-no additional cost of energy. These strategies mainly consist of the dilution and/or the capture and removal of contaminants at the levels of macroenvironment room air and occupant-adjacent microenvironment. On the macroenvironment level, the dilution occurs by the supply of large amounts of outdoor air in a sustainable way using passive cooling systems, and the removal of contaminants happens via filtering. Similarly, the microenvironment of the occupant can be diluted using localized ventilation techniques, and contaminants can be captured and removed by direct exhaust near the source of contamination. Thus, this work answers ten questions that explore the most prevailing technologies from the above-mentioned fronts that are used to mitigate cross-contamination in densely occupied spaces located in hot and humid climates at minimal energy consumption. The paper establishes a basis for future work and insights for new research directives for macro and microenvironment approaches.
... Natural ventilation is the main type of ventilation in residential buildings in most countries in the world [1]. But since it relies on natural conditions to create the pressure difference required to move the air, its performance strongly depends on the weather. ...
The paper presents the results of the experimental research on the air grills designed to stop backflows in natural ventilation stacks. For each grill pressure drop was measured for different airflow rates, in both flow directions. Two ∅ 100 mm grills working on different principles were tested: one with moving flaps, and one shaped in a way that should greatly increase the hydraulic losses during backflow. For comparison, the ordinary air grill was also tested. The results show that the grill with moving flaps works as intended. With only slightly higher hydraulic losses in the forward direction compared to ordinary grill, it shuts off the backflows almost completely. The other, diffuser-shaped grill doesn’t work as intended. It has very high hydraulic losses in both directions, and the effect of changing the air resistance with the reverse flow is barely noticeable.
... The experiments were conducted in a well-controlled steel chamber ( Fig. 1) with dimensions 2.56 m × 3.46 m x 2.29 m (W x L x H), corresponding to a total volume of 20.3 m 3 at the average experimental conditions of 25.6 • C, 42% RH, and AER of 0.51 h − 1 (full details in Table S1). The AER was selected using European building standards for ventilation in dwellings (Dimitroulopoulou, 2012). The conditions were monitored during each experiment. ...
Cleaning work using spray products has been associated with adverse respiratory effects but little is known of the exposure concentrations. The purpose of this study was to characterize aerosol generation at spray scenarios in a controlled climate chamber. Spraying on vertically and horizontally oriented surfaces, as well as spraying on a cloth, was investigated. Furthermore, the effect of nozzle geometry was tested. The average mass generation rates of six pressurized spray cans and 13 trigger sprays were about 1.7 g/s and did not differ significantly, but the average values of the individual sprays had large variations (0.5-3.1 g/s). The time required to halve the air concentration of aerosol particles, the half-life time, was determined for all spray products. The average half-life time of the total particle mass concentration (TPMC) of the pressurized spray cans was 0.5 h versus 0.25 h for trigger sprays. Gravimetrically determined airborne fractions of pressurized spray cans tended to be higher than those of trigger sprays. However, airborne fractions based on the measured peak TPMC were up to three orders of magnitude smaller. A comparison of different trigger spray nozzles when spraying the same product showed that the TPMC can be up to 18 times higher for the largest emitting nozzle. The distance of the nozzle to a cloth should be 1 cm to significantly reduce the concentration of the generated aerosols. ConsExpo modeling predicted the measured peak TPMC well but less well the decay.
... To ensure adequate IAQ in the European Union, EN15251 and EN 16798-1 give guidelines for indoor environmental criteria and building energy performance [7][8][9][10]. Some of these requirements are implemented in the building codes of the member countries [11]. However, even if the building ventilation system fulfils the requirements of the building codes in the design phase, system operation challenges may arise during the lifespan of the building. ...
High humidity inside ductworks could be a potential risk for microbial growth and there is also a hypothesis that lower night-time ventilation increases the risk of growth. This study investigates the possibility of microbial growth in ventilation ductwork exposed to humid and cold conditions. Two different typical night-time ventilation strategies for public buildings were investigated: ventilation rate was either continuously the same (0.15 L/s, m2) or no airflow during the night-time. Experimental data were collected over a four-month period. In the experiment, microbial media was released inside the ductwork initially. During the test period, air temperature and relative humidity inside the ductwork were controlled between 11–14 °C and 70–90%. Wipe, swab and air samples were taken at the beginning, monthly and at the end of the test period. The study results showed the extinction of colonies by the end of the experiment regardless of the chosen night-time ventilation strategy. The colony count in the air was low throughout the study period. Therefore, the results indicate that the long-term growth on the walls of air ducts is unlikely and the risk of microbial transfer from the air ductworks to room space is low.
... Ventilation practices can also differ between USA and Chinese residences; Chinese residences continue to heavily rely on natural ventilation modes (e.g., infiltration, windows) rather than mechanical ventilation systems [42]. It has also been shown that ventilation standards/regulations, as well as actual ventilation measurements in dwellings, vary across European countries [15]. Few studies in the current literature examined the details associated with gas cooking practices. ...
The most recent meta-analysis of gas cooking and respiratory outcomes in children was conducted by Lin et al. [93] in 2013. Since then, a number of epidemiology studies have been published on this topic. We conducted the first systematic review of this epidemiology literature that includes an in-depth evaluation of study heterogeneity and study quality, neither of which was systematically evaluated in earlier reviews. We reviewed a total of 66 relevant studies, including those in the Lin et al. [93] meta-analysis. Most of the studies are cross-sectional by design, precluding causal inference. Only a few are cohort studies that could establish temporality and they have largely reported null results. There is large variability across studies in terms of study region, age of children, gas cooking exposure definition, and asthma or wheeze outcome definition, precluding clear interpretations of meta-analysis estimates such as those reported in Lin et al. [93]. Further, our systematic study quality evaluation reveals that a large proportion of the studies to date are subject to multiple sources of bias and inaccuracy, primarily due to self-reported gas cooking exposure or respiratory outcomes, insufficient adjustment for key confounders (e.g., environmental tobacco smoke, family history of asthma or allergies, socioeconomic status or home environment), and unestablished temporality. We conclude that the epidemiology literature is limited by high heterogeneity and low study quality and, therefore, it does not provide sufficient evidence regarding causal relationships between gas cooking or indoor NO2 and asthma or wheeze. We caution against over-interpreting the quantitative evidence synthesis estimates from meta-analyses of these studies.
... The AER in this study is similar to several previous studies [14,17,[30][31][32][33]. The study in the natural ventilated bedrooms of 202 residences in Guangzhou in China found that their AERs ranged from 0.05 to 1.32 ACH (mean: 0.41 ACH) [14]. ...
It is difficult to accurately measure the air exchange rate (AER) in residential and office buildings during occupation via on-site field measurement. The tracer gas method was widely applied to estimate the AER in these buildings, and human metabolic carbon dioxide (CO2) was often used as a tracer gas in different models. This study introduced three models (the ASHRAE model, the ASHRAE China-specific modified model, and the BMR model), which were proposed to estimate the AER based on exhaled CO2. We verified these models by comparing the exhaled CO2-based AER with AER from field measurements using sulfur hexafluoride (SF6) as a tracer gas. We also analyzed the potential factors that could affect the uniformity of the indoor tracer gas distribution. Our results indicate that the ASHRAE China-specific modified model has the best performance with an average deviation of −6.67% and a maximum deviation of −14.6% with multiple measurement points, a stable personnel activity, and proper Parameter settings in a single room in China.
... Property type, construction date, and fuel type were also included in the analysis. The Standard Assessment Procedure (SAP) score [63], where 1 reflects the least energy efficiency of a property and 100 the maximum energy efficiency, was used as it may affect the air permeability of a property and therefore PM 2.5 concentrations [64]. Building information (type, date of construction, SAP score, fuel type) was provided by Coastline Housing and linked to the participant and sensor data. ...
(1) Background: Poor air quality affects health and causes premature death and disease. Outdoor air quality has received significant attention, but there has been less focus on indoor air quality and what drives levels of diverse pollutants in the home, such as particulate matter, and the impact this has on health; (2) Methods: This study conducts analysis of cross-sectional data from the Smartline project. Analyses of data from 279 social housing properties with indoor sensor data were used to assess multiple factors that could impact levels of particulate matter. T-Tests and Anova tests were used to explore associations between elevated PM2.5 and building, household and smoking and vaping characteristics. Binary logistic regression was used to test the association between elevated particulate matter and self-reported health; (3) Results: Of the multiple potential drivers of the particulate matter investigated, smoking and vaping were significantly associated with mean PM2.5. Following multivariate analysis, only smoking remained significantly associated with higher mean concentrations. Properties in which 15 cigarettes were smoked; (4) Conclusions: A total of 25% of social housing properties in this study experienced levels of indoor PM greater than WHO guideline levels for ambient air pollution. Although there are many factors that impact air quality, in this study the main driver was smoking. This highlights the importance of targeting smoking in indoor environments in future smoking cessation and control policy and practice and of understanding how pollutants interact in the home environment. There is also a need for further research into the impact on indoor air quality of vaping, particularly due to the rise in use and uncertainty of its long-term impact.
... It is therefore important to assess the level of fine and ultrafine particles (PM2.5 and PM1) in the air inside and outside classrooms, as well as identify practices that can improve air quality. Children's exposure depends on local outdoor air quality, indoor sources, and the ventilation system [Dimitroulopoulou, 2012]. Children's lungs can notably be irreversibly impacted by local tra c exposure, regardless of regional air quality [WJ et al., 2007]. ...
Les particules en suspension dans l'air (PM) sont aujourd'hui considérées comme un risque majeur pour la santé. Les enfants constituent l'un des groupes les plus vulnérables aux PM et à la pollution atmosphérique. Comme la majorité de la population passe plus de temps à l'intérieur, il est très important de connaître les différentes sources de particules dans cet environnement et la contribution des sources extérieures. Malgré les progrès réalisés dans la compréhension de la qualité de l'air intérieur, de nombreuses lacunes subsistent en ce qui concerne le transfert des particules de l'extérieur vers l'intérieur. Le magnétisme environnemental offre une grande opportunité pour l'étude des PM, car il est suffisamment sensible pour étudier les fractions les plus fines des oxydes de fer présents dans les PM. Les méthodes magnétiques sont également particulièrement adaptées pour être utilisées avec des biocollecteurs, échantillons naturels capables de retenir les polluants. Les biocollecteurs constituent une excellente alternative aux capteurs à faible coût, car ils sont rentables et ont un faible impact sur l'environnement. Ici, nous avons combiné des méthodes magnétiques avec des biocollecteurs afin de mieux comprendre le problème des PM intérieur-extérieur dans différents contextes urbains. L'objectif principal de la thèse était de caractériser les émissions anthropiques de PM à l'intérieur et à l'extérieur et la relation entre elles. Les différentes sources d'émissions urbaines ont été caractérisées dans des filtres PM2.5, fournissant des informations sur les propriétés magnétiques de ces sources, qui ont ensuite été utilisées dans l'étude des biocollecteurs. Les biocollecteurs ont été utilisés dans le cadre de projets scientifiques citoyens, afin d'étudier les PM dans les environnements urbains. Dans cette thèse, des techniques magnétiques innovantes ont également été utilisées pour étudier la fraction ultrafine des PM magnétiques. La microscopie électronique à balayage a fourni des informations morphologiques complémentaires sur les oxydes de fer et les autres constituants des PM. Les résultats indiquent tout d'abord que les différentes sources d'émissions anthropiques présentaient une distribution granulométrique étroite. Pour la ville de Toulouse, les émissions dues au trafic routier ont dominé la fraction magnétique des PM qui sont transportées à l'intérieur des habitations. Des sphérules d'oxydes de fer ultrafines d'environ 50 nm (et plus) liées aux émissions du trafic, ont été détectées au MEB. L'environnement intérieur présente une concentration plus faible de PM magnétiques (avec des I/O moyens pour le SIRM compris entre 0,7 et 0,9 pour les écoles et de 0,5 pour les résidences). La fraction granulométrique est plus fine par rapport à l'extérieur (dans le SSD). La fraction ultrafine pour ce type de grain a un diamètre moyen calculé à 7.7nm. D'autres sources de particules, outre les émissions du trafic, sont également importantes à l'intérieur, notamment dans l'environnement scolaire, comme le montrent les I/O pour la concentration de carbone organique allant de 1,1 à 1,9. Avec l'hypothèse que certaines des particules PM émises en milieu urbain sont entraînées dans le cycle de l'eau, les sédiments de la Garonne ont été étudiés. Les résultats montrent des pics de susceptibilité magnétique (atteignant des valeurs de 2,95x10-6) et de métaux traces (tels que Cu et Pb atteignant des concentrations de 139,0 et 73,5 ppm) dans le centre-ville de Toulouse qui indiquent un apport anthropique. La présence de sphérules d'oxydes de fer de taille micrométrique (allant de 10 à 91 um) montre que les sources d'émission liée au trafic routier sont à l'origine des particules détectées. En conclusion, cette thèse a fourni de nouvelles informations sur les émissions anthropiques de particules et sur leur relation intérieur-extérieur, qui peuvent être utilisées pour caractériser la qualité de l'air dans les environnements urbaines.
... The latest regulatory revisions have taken both aspects into account, and propose mechanical or hybrid ventilation systems, so as to compensate for the greater thermal insulation of both opaque enclosures and opening systems, including carpentry [13,14]. However, the big problem persists in existing homes [12] which, as already mentioned, in Spain are more than 90%, with poor levels of thermal comfort and insulation [15], and that, despite being candidates for national and European fundings [41,42], many of them are limited to technical responses of insulation from the outside, and/or change of windows, but they do not solve the problem of air infiltrations, nor the control by ventilation systems that might ensure a correct balance with possible support air conditioning equipment. ...
Since SARS-CoV-2 spread worldwide in early 2020, many countries established lockdowns for protection. With a main transmission by aerosols, ventilation was promoted. This article analyses natural ventilation of Spanish housing during the spring 2020. An online questionnaire was launched, obtaining for this study 1502 responses. The comparative window opening before and during confinement and households, dwellings and home activity variables, were analysed. The binary logistic regression model before pandemic, indicated that ventilating properly related to: a worse perceived IAQ (OR = 1.56); thermal adaptation measures, especially those that prefer to open/close windows (OR = 1.45); not having heating system (OR = 1.15); and using power to heat water (OR = 1.60). For the confinement period, the model highlighted: being an employee (OR = 1.88); using heavy clothing in the home (OR = 2.36); and again, open/close windows for adaptation (OR = 2.24). According to specific tasks in quarantine, frequent ventilation was boosted by: an increasing use of oven (OR = 14.81); and alteration of work-habits (OR = 2.70), sport-habits (OR = 1.79), and outdoor-activities (OR = 1.60). Thus, an adequate natural ventilation pattern during the quarantine linked to low environmental comfort in general, by virtue of indoor air quality. This is corroborated by less acoustic-thermal insulation, worse indicators of heating use, and the adaptive response to opening/closing windows when external temperature changed.
... Studies on indoor radon concentration in dwellings in China have shown that the main source of radon entry is from the soil, followed by building materials, water and other secondary effects (Li et al., 2006;Ye et al., 2017;Su et al., 2022). For multiple-story buildings, the soil source remains important, depending on ventilation rate and exchange rate between stories of the building (Nazaroff, 1992;Bekö et al., 2011;Ramola et al., 2011;Dimitroulopoulou, 2012;Girault and Perrier, 2012). ...
The inert radioactive gas radon-222, ubiquitous in the environment, is the first cause of lung cancer in non-smokers and a powerful asset to trace geological fluids and constrain atmospheric transport models. In all of these applications, radon flux (RF) from the ground needs to be estimated. However, obtaining a large-scale representative estimate of RF in continental land is a challenging task and a starting basis is to focus on large countries in the world. Here, we collected a total of 2622 direct RF measurements carried out in continental China from 1988 to 2021 using 69 publications in a 494-document pool. Over the whole dataset, the RF results were classified into geographical provinces, time periods and substratum types. Mean RF values yield 180±32, 36.9±4.8, 31.1±1.0, 66.1±1.6 and 1510±100 mBq m⁻² s⁻¹ in metamorphic and igneous (n=71), sedimentary (n=24), Quaternary (n=585), faulted areas (n=832) and uranium-related sites (n=898), respectively. Considering geology only, mean RF for China (66±11 mBq m⁻² s⁻¹) is larger than most large-scale estimates worldwide. To account for the distribution of soil thickness, RF values were extrapolated to representative soil thickness values per lithology using a scaling law inferred from natural sites. The inferred corrected mean RF for China yields 20.2±6.1 mBq m⁻² s⁻¹, corresponding to a total radon-222 emission of (191±43) × 10⁹ Bq s⁻¹, and appears compatible with available large-scale estimates in Europe or at global scale. Potential sources of systematic bias and variability, such as vegetation cover, meteorological and seasonal effects, remain. The contribution of urban areas, estimated for the first time, was found significant. Our study suggests future research directions to better constrain the RF source to the atmosphere in China, and, more generally, to extract robust global-scale representative RF values from direct RF measurements.
... • A leak rate of 0.5 h −1 through windows, doors, and other openings, which is a typical value for European houses [62]. ...
Indoor air cleaners can contribute to reducing infection risks by the filtration of virus-carrying droplets. There are various national standards to test indoor air cleaners that determine the clean air delivery rate (CADR), but typically only as a size-integrated value for particles >0.3 μm. Thus, a test method using potassium chloride (KCl) and paraffin as surrogate particles in the size range of viruses and exhaled droplets was developed. We show that air cleaners with fibrous and electrostatic filters are generally capable of reducing the airborne particle concentrations. However, for electret filters, the performance can strongly degrade over time by being loaded with particles. By comparing filters with different efficiencies in the same air cleaner, we demonstrate that the use of high-efficiency filters can be even at the expense of the cleaning efficacy. We developed a mathematical model to estimate the inhaled dose of viruses and show that the combination of natural venting and an air cleaner can lead to a substantial reduction of the infection risk.
... Children's exposure depends on local outdoor air quality, indoor sources, and the ventilation system (Dimitroulopoulou, 2012). Children's lung can notably be irreversibly impacted by local traffic exposure, regardless of regional air quality (Gauderman et al., 2007). ...
Children's exposure to air pollution affects both their health and learning skills. Fine and ultrafine particulate matter (PM2.5, PM1), notably issued from traffic sources in urban centers, belong to the most potential harmful health hazards. However their monitoring and the society's awareness on their dangers need to be consolidated. In this study, raising teacher and pupil involvement for air quality improvement in their schools environment is reached through developing a passive monitoring technique (bio‐sensors made of tree bark). The experiment was implemented in two urban elementary schools situated close to a main traffic road of the city of Toulouse (South of France). Magnetic properties, carbonaceous fraction measurements, and scanning electronic microscopy (SEM‐EDX) investigations were realized both on passive bio‐sensors and filters issued from active sampling. We find that traffic is the main PM1 source for both outdoors and indoors at schools. Higher levels of outdoor PM in the school's environments compared to urban background are reached especially in the cold period. The schools proximity to a main traffic source and lack of ventilation are the main causes for observed PM1 accumulation in classrooms. The co‐working experiment with educational teams and pupils shows that the use of bio‐sensors is a driver for children empowerment to air pollution and therefore represents a potential key tool for the teachers though limiting eco‐anxiety. As PM accumulation is observed in many scholar environments across Europe, the proposed methodology is a step toward a better assessment of PM impact on pupil's health and learning skills.
... In the current study, the choice was made to fix the air-exchange rate v at 0.5 h -1 , a conservative value for dose evaluations representing poor ventilation. This value is reasonable considering the experimental studies on air-exchange rates in the United States as summarized in Yu et al (2003, section J.2.6) and a more recent review on ventilation rates in European dwellings by Dimitroulopoulou (2012). Skin contamination of hands and face by transfer (object-to-hand and hand-to-face) is a process determined by both the particular use of the object and the physical and chemical properties of the object and contaminants. ...
This paper provides surface-clearance levels for 413 radionuclides for the normal reuse of objects leaving the controlled area of a nuclear facility. Four sets of surface-specific clearance levels are derived based on choices of dose coefficients in probabilistic dose assessments using the SUDOQU model (van Dillen and van Dijk 2018). The general dose criteria for clearance, extended with a suitable dose constraint for the concept of the representative person, are applied in the derivations. These clearance levels apply to the total of fixed and removable radioactive contamination on the surface of objects. Results are discussed in the context of conservatism of the exposure scenarios (parameters, dose coefficients), and guidance is given on the selection and application of the values.
... The energy use of the barber shop including the systems is calculated according to DIN V 18599 (11) using the Energieberater 18 599 3D PLUS software (12). As no specific electrical appliances (such as hairdryers) can be simulated in the Energieberater, the electricity consumption of this equipment is estimated based on a site visit of a (small) barber shop and combined with the energy use as output from the simulation model. ...
A major target of the European Green Deal is to raise the 2030 greenhouse gas emission reduction target to 55% compared to 1990. This high ambition includes an increase of the energy performance of buildings and additional generation of renewable energy in all sectors. The tertiary sector, including small and medium sized enterprises (SMEs) such as butchers, small food and non-food shops, restaurants and pubs, is one of the sectors that can contribute to this goal. While large companies in this sector are regularly in the news with iconic projects, for many SME owners "sustainability" is not a key issue. Reasons are that 1) they are not aware of interesting technologies or business cases specific for their company, 2) they are focused on their own business operation and 3) do not always own the building. That is why the Flemish-Dutch TERTS project strives for a transition in energy use and production by 1) demonstrating cutting-edge (innovative) technologies (e.g. circular isolation materials, heat pumps etc.) in SMEs and 2) by guiding these SMEs. This study assesses the impact of different (innovative) technologies specific for the target group 'barber shops'. A reference building is made by analysing 60 existing barber shops in Flanders. The energy use of the barber shop including the systems is calculated according to DIN V 18599 using the Energieberater 18 599 3D PLUS. Subsequently, the cost-benefit of various measures is calculated and compared. This provides us with an approach that not only includes financial measures but also takes metrics into account for CO2 reduction and comfort. Several technologies, which only have moderate financial benefits, reach acceptable overall satisfaction due to the inclusive metrics. This approach is based on modern business model developments and offer SMEs a more qualitative and inclusive way of the return of innovative technologies to support their investment decision making.
... Occupants are also the source for some of the pollutants under consideration, so the generation rates are dependent on the occupant influence. Poor ventilation practices have been shown to be linked to poor health outcomes, and whilst these are often associated with increasingly airtight buildings, the influence of the occupant on the overall ventilation rate was observed [20]. ...
Sealing the gaps in a house, or increasing airtightness, is a common approach to reduce energy consumption, as well as make the house more comfortable to live in. However, people need a certain amount of fresh air in their homes to maintain air quality, and concerns have been raised that increased airtightness may have the unintended consequence of reduced indoor air quality (IAQ). This rapid review identified 20 studies that investigated the impact of increasing airtightness on indoor air quality. These studies covered a broad range of locations, climates and building types. Indoor air quality parameters investigated included CO2, PM2.5, formaldehyde, VOC, NO2, relative humidity, mould issues, carbon monoxide (CO) and radon. Based on the studies reviewed, there was limited evidence to identify direct correlations between increasing airtightness and indoor air quality in general. A negative correlation with CO2 concentration was found from the studies, with concentrations increasing with a decrease in the air tightness levels. There was evidence of a negative correlation for VOC and formaldehyde, although a number of studies found no clear relationship for these parameters and further studies would be required to understand this impact. A positive correlation was found between the air exchange rate and PM2.5 and NO2 concentrations in areas where there are high outdoor levels. In these cases, increasing airtightness was found to reduce the infiltration of outdoor contaminants. There were no direct correlations identified for mould issues, radon or CO, or for PM2.5 or NO2 in areas with average outdoor levels.
... Indoor air quality influences and affects, like the other environmental factors explained above, the well-being of the older adult population. Dimitroulopoulou [34] states that ventilation is recognized as an important component for a healthy home, since it is possible to associate poor/inadequate ventilation with indoor air pollution and, consequently, health problems. The indoor air quality and its impacts, particularly in situations where the occupants are most vulnerable (elderly population), can be quantified and solutions can be prescribed, both for the occupants and for the building itself (e.g., improved ventilation of spaces) [35]. ...
The SAVING project aimed to create a sustainable and active aging program to promote the transition to sustainable aging in residential structures for the elderly (RSEs), developing research activities to apply the best strategies and good practices regarding the promotion of an active, healthy, and sustainable aging regarding social, economic, environmental, and pedagogic aspects. All this innovative methodology was built on a living-lab approach applied in one RSE, that was used as a case study. The results showed that the creation of the SAVING Brigade allowed not only increased reflection and mutual learning, but also created better conditions to face uncertainties and obstacles. Moreover, the use of indicators supported the basic themes and enabled comparison with other studies, between institutions or programs. Finally, the Action Plan acted as a tool for the development of previously defined strategies. It is possible to conclude that the breadth of the concept of quality of life encompasses the physical health of the individual, their psychological state, their social relationships, their perceptions, and the relationship with the characteristics of the context in which they are inserted. Therefore, active, sustainable, and healthy aging should be the goal.
... Firstly, all windows are closed for 20% of the occupied time and less than 5% of the unoccupied time in Flat A (Figure 1 -WO: None; DO: All). Only three ventilation measurements were taken in this configuration, but all were below 0.5 h -1 , which is often considered a threshold for adequate ventilation (Dimitroulopoulou, 2012). The vast majority of the ventilation rates measured in all other configurations were over 0.5 h -1 (accounting for the configurations during 80% of the occupied time), at least one window was open in all these configurations. ...
Ventilation in dwellings is likely to be impacted by configurations of windows and internal doors, but there is little empirical research investigating this in occupied homes. Closure of internal doors will affect noise, light, heat flow and how air moves into and through a building, as well as the volume of air in which pollutants are diluted. However, most ventilation measurements in homes have either conducted long-term averages in which the effect of use of windows and doors is not addressed, or small numbers of 'snap-shot' measurements in which the distribution of ventilation rates in particular configurations is not known; this reduces our understanding of environmental quality at home. This paper reports the detailed investigation of window and internal door use and their link to ventilation measurements in two occupied flats in the same building over six months. Doors and windows were monitored using event-logging contact sensors and CO2 was measured in all rooms. An algorithm for determining occupied periods was used and ventilation rates were estimated using the CO2 decay technique during unoccupied times. In one of the flats almost 70% of the ventilation measurements were less than 0.5 ach in the configuration in which the occupant spends 55% of their time while at home; in the other flat windows were open for 80% of the occupied time and 90% of the ventilation rates measured with windows open were above 0.5 ach. The dwellings were physically similar, equipped with the same ventilation equipment and subject to the same weather. These results highlight the importance of considering the extent to which conditions during measurement periods (or modelled conditions) reflect the conditions that occupants experience. Further research employing methods able to characterize ventilation in homes and distinguish between occupied and unoccupied times, contextualized by measuring configurations of doors and windows, will support greater understanding of ventilation in dwellings. This could provide insights into the real conditions in homes, supporting effecive modelling and design. Such detailed research would support developments in practice and policymaking, by helping to disentangle the related issues of ventilation rates, indoor pollution, personal exposure to pollutants and the effects of these on health outcomes.
... However, the latter is only applicable in areas with low levels of ambient pollutants. 23,24 In cases where source control and natural ventilation are not effective control strategies, using range hoods over the stove and portable air cleaners near the receptor can be a good alternative to reduce PM 2.5 exposure. [25][26][27][28][29][30] In terms of control strategies, AQMs provide an opportunity to alert consumers about degrading levels of air quality in their homes and enable them to perform some of these mitigation strategies. ...
In this study, we deployed multiple low-cost air quality monitors (AQMs) to investigate the transport of kitchen-generated fine particulate matter (PM2.5) into the bedrooms of four homes of different sizes over a period of more than nine weeks at each home. We also estimated the human exposure to PM2.5 associated with each microenvironment and evaluated the effects of using a portable air cleaner (PAC) to reduce those exposures. To select the best AQM for these analyses, we compared the field response of five commercially available models with that of a research-grade optical particle spectrometer. The AirVisual AQM showed the best correlation during collocation phases with R² values in the range of 0.5-0.9 during cooking and background periods for all locations. The bedroom monitors picked up cooking emissions from the kitchen area within 1-45 min depending on the layout of each home, and median PM2.5 concentrations in the bedroom were up to 30% lower than those in the kitchen. Results from the exposure analysis suggest that PAC use is an important intervention strategy for reducing personal PM2.5 exposure, especially in indoor environments where cooking is the main source of PM2.5 concentrations. In three of the four homes using PAC consistently in the kitchen or bedroom area during intensive cooking periods reduced overall exposure values by 30-90%. Moreover, during nighttime periods, PAC usage in the bedroom area yielded the lowest levels of PM2.5 exposure for all the homes.
... h -1 in apartments and 0.45±0.22 h -1 in houses in Europe [9], in which AER <0.5 h -1 occupants are more likely to experience non-specific symptoms. ...
Houses are the places where people spend most of their time. That is why indoor air quality at home is essential for public health. Sufficient ventilation is the factor to avoid accumulation of pollutants in indoor air, which include microorganisms, such as SARS-CoV-2. Therefore, adequate ventilation is needed to provide good indoor air quality for human health and reduce infection risk at home. There are no reports of residential ventilation rates in Turkey. In this study, CO2 concentrations were measured in two residences in Izmir, Turkey. Three experiments were conducted to determine background concentrations and the rate of natural ventilation with infiltration and opening windows. Results show that air exchange provided by infiltration is low for both case rooms, while adequate ventilation could be achieved with natural ventilation under the studied conditions. Infiltration provided air exchange and ventilation rates of 0.18 h-1 and 5.9 m3/h for Case 1 and 0.29 h-1 and 8.23 m3/h for Case 2, respectively. Airexchange and ventilation rates were increased to 2.36 h-1 and 76.9 m3/h for Case 1 and 1.2 h-1 and 34 m3/h for Case 2, respectively, by opening the windows. Although ventilation can be
provided by opening the windows, the other factors that determine its rate, e.g., meteorological variables, cannot be controlled by the occupants. Consequently, people cannot ensure the good indoor air quality in bedrooms and sufficient reduction in transmission of pathogenic microorganisms; therefore, risk of spreading diseases such as COVID-19 at home.
... Poor ventilation itself increases the risk of death regardless of socioeconomic status [54]. Along with crowding, poor ventilation has been identified as having negative effects on health; ventilation regulations differ from country to country and by the space in the house and are not easy to quantify [55]. Assessing ventilation with the presence of a window alone is inappropriate. ...
Background
Tuberculosis (TB) is a global health issue that has long threatened and continues to threaten human health. While previous studies are important in the search for a cure for TB, to eradicate the disease it is also crucial to analyze environmental influences. Therefore, this study determined the potential effect of inadequate housing on TB and the magnitude of the effect.
Methods
This is a systematic review of the effects of inadequate housing on TB. Between Jan 1, 2011 and Oct 25, 2020, we searched four electronic databases using the search terms “housing AND tuberculosis” or “housing AND TB”. The target population comprised residents of inadequate housing and the homeless.
Results
We found 26 eligible studies. The distribution of the studies across continents was uneven, and the housing issues of interest seemed to vary depending on the economic level of the country. The eight steps identified in TB development and the consequences thereof were more strongly associated with housing affordability than with housing quality.
Conclusions
This is the first systematic review to identify the effects of inadequate housing on TB and to categorize inadequate-housing-related exposure to TB in terms of affordability and quality. The steps identified in TB development and the consequences thereof had a greater association with housing affordability than with housing quality. Therefore, public health interventions regarding housing affordability could be more diverse, and interventions that support affordable housing for residents of inadequate housing and the homeless should proceed simultaneously to improve housing quality.
... While the airtightness of retrofitted energy-efficient buildings might limit the infiltration of outdoor pollutants, the resulting reduced ventilation can have unwanted repercussions on indoor air quality (IAQ) [33] and adverse effects on respiratory health [34][35][36]. When the household air changes per hour (ACH) fall below the European standard of 0.5 ACH [37], this results in the accumulation of most indoor pollutants-including bacteria that are closely related to human pathogens [38]-and an increase in the relative humidity of the ambient air, which favors the development of molds [36,39]. Indoor air temperature also matters, as it regulates the relative humidity content and can promote the release of pollutants from building materials. ...
Improving the energy efficiency of buildings is a major target in developed countries toward decreasing their energy consumption and CO2 emissions. To meet this target, a large number of countries have established energy codes that require buildings to be airtight. While such a retro-fitting approach has improved health outcomes in areas with heavy traffic, it has worsened the health outcomes in Nordic countries and increased the risk of lung cancer in areas with high levels of radon emissions. This review highlights the importance of adapting the characteristics of energy-efficient residential buildings to the location, age, and health of inhabitants to guarantee healthy indoor pollutant levels. The implementation of mechanical ventilation in new energy-efficient buildings has solved some of these problems; however, for others, a decrease in the level of outdoor pollutants was still required in order to achieve a good indoor air quality. A good balance between the air exchange rate and the air humidity level (adapted to the location) is key to ensuring that exposure to the various pollutants that accumulate inside energy-efficient buildings is low enough to avoid affecting inhabitants′ health. Evidence of the protective effect of mechanical ventilation should be sought in dwellings where natural ventilation allows pollutants to accumulate to threatening levels. More studies should be carried out in African and Asian countries, which, due to their rapid urbanization, use massive volumes of unproven/unrated building materials for fast-track construction , which are frequent sources of formaldehyde and VOC emissions.
... Thus, a high degree of privacy is enhanced. Besides, Dimitroulopoulou [11] says that insulating ventilation is another premium activity which contributes much to a building's-maintained privacy level. ...
... Therefore, the indoor "in-person" life must come with strategies ensuring safety of people, specifically in highly occupied spaces such as school and university classroomsthe places where investment in the future of the community occurs. The main acknowledged measures that limit the spread of viruses involve maintaining physical distancing (in the range of 2-m) [3] and improving ventilation indoors by increasing the ventilation rate to a sufficient level [1,4,5]. ...
This work investigates the performance of a novel chair-ventilation design integrating ductless personalized ventilation (PV) and personalized exhaust (PE) in a classroom conditioned by displacement ventilation (DV). The aim is to protect seated students and restrict contaminants' transport in high-density classroom where students are seated at a typical separating distance of 0.4 m. A 3-D computational fluid dynamics model was developed and experimentally validated in a climatic chamber including a prototype of the proposed ventilation system. The cross-contamination was assessed using the inhaled intake fraction (iF) index, which is the ratio of the contaminants’ mass inhaled by an exposed person to that exhaled by an infected person. The proposed system effectiveness was assessed via an exposure reduction index (ER) when compared to “no chair ventilation” case at the same separating distance of 0.4 m, as well as a “large distancing” case at separating distance of 2 m in a room that is only ventilated via DV.
It was found that the proposed chair system protected exposed occupants against cross-contamination. The chair system, compared to the no chair ventilation case, was able to reduce the exposure level of students due to the combined protective roles of the dilution of breathing zone (BZ) by the PV flow and the shielding effect of the PE flow. By comparing the proposed system to the large separating distance case, it was still able to provide similar and even higher protection levels for all students when both PV/PE systems operated at flowrates higher than 6 l/s.
... Adequate ventilation is essential for the health and comfort of building occupants [38]. As buildings have become more air-tight over recent years, but also because of the Covid-19 pandemic, minimum ventilation rates have become more strict [39][40][41]. ...
At present many buildings, that are not able to meet the changing needs of owners and users, are demolished before they reach their technical lifespan. To avoid such waste, the construction industry is shifting to adaptable building practices. Comfort systems in buildings that can effectively deal with an adaptable context are critical to the success of this transition. After all, these systems must ensure that the health and comfort of occupants is guaranteed in all possible flexibility scenarios. In practice, comfort systems that provide ventilation strongly adhere to firmly rooted approaches with limited adaptability. Moreover, implementing adaptability does not happen at the conceptual level, but is achieved by oversizing components and incorporating demand control. Alternative ventilation systems that are conceptually more compatible with an adaptable context are rarely even considered. To fill this knowledge gap, this review article identifies and uses various adaptability characteristics of ventilation systems to qualify both contemporary and innovative ventilation systems based on their ability to facilitate a flexible building use. By juxtaposing the systems, the article goes beyond the state-of-the-art and learns from the meta-level rather than individual cases. It is concluded that traditional ventilation strategies do not provide the most appropriate solution for an adaptive context, that bulky ductwork is incompatible with long-term flexible building use, and that specific guidelines for designing adaptable ventilation systems are lacking. Further research should look into this and additionally quantify the environmental and financial benefits of adaptable ventilation systems through life cycle assessment and life cycle cost evaluation.
... The preferable indoor air quality and airflow rates are presented in the EU directives, binding for EU countries and standards. They are presented in such documents as Energy performance of buildings directive with levels of Energy performance Certification, EN 16798-1 standard in general, and EN 15214 in specific for the IAQ (indoor air quality) [3][4][5]. Most recommendations and buildings codes consider the minimum airflow rate, temperature level and CO 2 concentration. ...
The paper analyses the performance of a five-storey apartment building equipped with modern passive stack ventilation in Nordic conditions. The passive stack ventilation system was retrofitted in 2019, and novel self-regulating air inlet devices with filters were equipped. The building was simulated with IDA ICE software, where the model of the self-regulating terminal units was developed using manufacturer product data. Several case scenarios were created to analyze the effects of poor maintenance, improved airtightness, and window opening on the system performance. For the analysis, one-room and three-room apartments on the second and fifth floors have been chosen. The CO2 concentration and indoor air temperature were analyzed and compared with EN 16798-1 standard guidelines. The results show a significant effect of poor maintenance and possibility to open windows on the CO2 concentration. The results also show a trend for the one-room apartments to overheat despite having a higher air change rate than the three-room apartments. The three-room apartments tolerate over-heating, although they are much more sensitive to poor maintenance. Furthermore, the apartments on the fifth floor are even more sensitive to poor maintenance, and three-room apartments there showed warning levels of CO2. Improving the envelope airtightness does not benefit the IAQ of the apartments.
... Finally, the air exchange rate, a, is considered a critical exposure factor that may potentially modify health effect estimates reported in epidemiological studies (Long and Sarnat, 2004). However, studies show significant variation in air exchange rates, both in time and between buildings, countries and occupants (Dimitroulopoulou, 2012;Dimitroulopoulou and Bartzis, 2014;Øie et al., 1998). Further, measurements of representative air exchange rates are subject to significant uncertainties, particularly regarding occupancy, multizonal airflows, sensor accuracies, temporal variations and analytical methods (Batterman, 2017;Johnston and Stafford, 2016;Kabirikopaei and Lau, 2020). ...
Long term, continuous indoor and outdoor pollutant monitoring was evaluated from a case study hospital, school, office and 18 apartments in the UK. Data was examined in order to explore the dynamic behaviour of indoor-outdoor ratios (I/O) for both particulate matter and nitrogen dioxide. Traditionally I/O ratios have been determined as single aggregate values or static parameters, from passive sampling or short periods of continuous monitoring. Whilst widely reported, I/O ratios are seen as too variable to be of wider use. However, this work reveals the dynamic nature of I/O ratios, with strong diurnal and seasonal variation observed for both particulate matter and nitrogen dioxide. Higher I/O ratios tended to be seen during core or occupied hours, associated with increased human activity and higher ventilation rates. This means that static I/O ratios determined by passive sampling techniques, rather than continuous measurements filtered to core hours, may underestimate I/O ratios associated with occupant exposure. Further, the I/O ratio is shown to be strongly influenced by occupant activity and window opening behaviour. As such, it may represent a personal variable as much as one associated with a building. It is argued that traditionally reported static I/O ratios simplify these dynamic behaviour and modes of operation into a single aggregate value, losing key information in the process. Further, without contextual information on the operation and use of a building during measurements a reported I/O ratio may be hard to interpret or compare to wider studies. Finally, it is argued that the I/O ratio, whilst a limited metric, when evaluated dynamically provides a useful building operation parameter, describing the relationship the building has with the outdoor environment. This can help better define ventilation strategies, schedules, the influence of occupant behaviour and significance of indoor sources.
... Therefore, sufficient air ventilation is prudent for indoor buildings. The ventilation system is functional to introduce the circulating of fresh air throughout the building by eliminating the indoor air contaminants to achieve good indoor air quality, to lower the health risk problems among the occupants 14 and to lower the indoor temperature. 15 Besides that, natural ventilation could improve IAQ, thermal comfort, reduce energy consumption, and provide comfort for building occupants. ...
This study observed the influence of different ventilation, indoor and outdoor activities (i.e., cooking, praying, sweeping, gathering, and exhaust from motorcycle) between a bungalow house (i.e., stack and cross ventilation applications) and a terrace house (i.e., one-sided ventilation application). We appraised the indoor air quality (IAQ) and thermal comfort. We monitored the indoor air contaminants (i.e., TVOC, CO, CH2O, PM10, O3, and CO2) and specific physical parameters (i.e., T, RH, and AS) for four days in the morning (i.e., 6.00 a.m. – 9.00 a.m.), morning-evening (i.e., 11.00 a.m. – 2.00 p.m.), and evening-night (i.e., 5.00 p.m. – 8.00 p.m.) sessions. The results found that cooking activities are the major activities that contributed to the increase of the TVOC, CO, PM10, O3, and CO2 concentrations in the bungalow and terrace houses. However, IAQ exceeded the Industry Code of Practice on IAQ (ICOP) limit in the terrace house. The bungalow house applies stack and cross ventilation, double area, and a long pathway of indoor air contaminants movements. Besides that, the results indicated that cooking activities worsen the ventilation system because CO2 exceeded the ICOP limit on Day 2 at 74.1 % (evening-night session) and Day 3 at 13.2 % (morning session), 11% (morning-evening session), and 50.1 % (evening-night session). Moreover, the combination of mechanical (i.e., opened all fans) and natural ventilation (i.e., opened all doors, windows, and fans) is the best application in the house without a cooking ventilator with lower indoor air movement. Furthermore, the temperatures exceeding the ICOP limit of 23-26 °C for both bungalow and terrace houses could be lower indoor air movement, which is less than the ICOP limit of 0.15-0.5 m/s and high outdoor air temperature. Therefore, it is prudent to have an efficient ventilation system for acceptable indoor air quality and thermal comfort in the family house.
... Poor quality housing with leaks, draughts, poorly insulated walls is likely to benefit from shallow and medium insulation levels in eliminating the dampness problem. But as insulation level is increased the relationship maybe reversed -with increasing indoor air tightness, indoor humidity sources may not be dispersed well enough and may start to cause mould growth (Dimitroulopoulou, 2012). The relationship between housing insulation levels and indoor dampness may take a shape of letter U with an optimum situation around the middle -medium levels of insulation. ...
The main objective of the COMBI project (Calculating and Operationalizing the Multiple Benefits of Energy Efficiency in Europe) was to capture the multiple impacts of energy efficiency while using the same energy activity data in various fields of research and policy: air pollution, resource efficiency, social welfare, economy and energy system/security. This report has been renamed to reflect a narrower scope adopted for the social welfare work package – public health co-benefits in relation to energy poverty. Air pollution-related public health aspects have been explored in COMBI report D3.4.
According to the European Union’s Survey on Income and Living Conditions (EU SILC), 9.4% of European Union’s population were unable to keep their homes adequately warm and 15.2% lived in residential housing characterized by a leaking roof, damp walls, floors or foundation, and rot in window frames or floors in 2015 – base year for COMBI assessment. Indoor cold is related to excess morbidity and mortality due to respiratory and cardiovascular diseases during the cold season. Indoor dampness is related to mould growth, which in turn may give rise to asthma. Energy efficiency measures applied in the existing residential housing, such as building envelope insulation, replacement or installation of heating, ventilation and air conditioning systems are believed to mitigate the extent of these health conditions. Improved energy efficiency standards of new buildings are believed to prevent from energy poverty-related health implications.
This report quantifies the impact of energy efficiency interventions on energy poverty-related public health conditions – excess cold weather deaths due to indoor cold exposure and asthma due to indoor dampness exposure. To evaluate the current extent of burden of disease in relation to these residential housing-related conditions, the standard excess winter deaths formula has been further developed to account for recent methodological criticism – excess cold weather deaths have been quantified instead. Burden of disease approach has been used to evaluate the extent of asthma morbidity due to indoor dampness. The future projections assumed that the annual burden of disease remained the same in relation to all other factors with the exception of changes in the two factors at the focus of COMBI – indoor cold and indoor dampness (ceteris paribus). The prevalence of indoor cold and indoor dampness is modelled in relation to the extent and type of changes in the residential housing stock and the extent of social welfare policies.
Excess cold weather deaths accounted for around 323 000 cases annually in 1996-2014 in the EU-28. Out of those, around 70 000 on average annually could be attributed to indoor cold exposure. The burden of disease of asthma attributable to indoor dampness amounted to over 71 000 Disability Adjusted Life-Years (DALYs) in 2015 in the EU-28.
There is a mismatch between those who can afford energy efficiency retrofits and those who need them the most and would benefit from them the most (not only energy savings, but also improved health). Comparing the extent of the energy efficiency interventions in the residential sector under both scenarios in 2030 and the current prevalence of indoor cold and indoor dampness, in theory diverting all of the projected resources to the socially vulnerable should eradicate nearly all premature excess cold weather deaths and indoor dampness-related asthma (“socially vulnerable first” social policy scenario). The societal value of public health co-benefits would be maximized.
The public health impact of energy efficiency improvement actions in 2030 in the EU-28 ranges from a minimum of just over 3 000 of premature deaths avoided due to indoor cold under COMBI reference scenario coupled with a weak social policy to around 27 500 of avoided premature deaths under COMBI efficiency scenario coupled with a strong social policy; and a minimum of 2 700 DALYs of asthma morbidity avoided due to indoor dampness under COMBI reference scenario coupled with a weak social policy to around 25 000 DALYs under COMBI efficiency scenario coupled with a strong social policy.
The associated economic value of avoided annual public health damage in 2030 ranges from 323 million EUR to 2.5 billion EUR due to premature mortality due to indoor cold; and from 338 million EUR to of 2.9 billion EUR due to asthma morbidity due to indoor dampness.
Accelerated energy efficiency policies coupled with strong social policies could deliver additional co-benefits in the year of 2030 of around 24 500 avoided premature deaths due to indoor cold and the associated avoided economic damage of 2.2 billion EUR, and around 22 300 DALYs of avoided asthma due to indoor dampness and the associated avoided economic damage of 2.6 billion EUR.
The world is facing a rapid increase of air conditioning of buildings. It is the motivation of Annex 80 to develop, assess and communicate solutions of resilient cooling and overheating protection. Resilient Cooling is used to denote low energy and low carbon cooling solutions that strengthen the ability of individuals and our community to withstand, and prevent, thermal and other impacts of changes in global and local climates. It encompasses the assessment and Research & Development of both active and passive cooling technologies of the following four groups: Reduce heat loads to people and indoor environments. Remove sensible heat from indoor environments. Enhance personal comfort apart from space cooling. Remove latent heat from indoor environments. The present review sums up the state of the art in cooling solutions which may be regarded as resilient. Its main objective is to systematically describe the available cooling solutions, their physical basis, their benefits and limitations, their technology readiness level, their practical availability, and applicability. Doing so, the State-of-the-Art Review forms the basis for the work of EBC Annex 80.
Stricter energy efficiency requirements of buildings have raised concerns about their effects on indoor air quality (IAQ). We studied measured and perceived IAQ in three low-energy wooden test buildings using three ventilation levels (0.5, 1.0, and 2.0 (dm³/s)/m²). IAQ measurements included VOC (volatile organic compounds) air sampling and continuous measurements of several IAQ indicators. Perceived air quality (PAQ) was investigated with a sensory panel of untrained volunteers. The results show that the TVOC (Total VOC) concentrations were relatively low in two of the buildings already at the beginning of the study (100–141 µg/m³), and the concentrations decreased in all test buildings when ventilation was increased from the lowest level. The third building made of pinewood timber showed higher VOC concentrations (340–857 µg/m³), especially for terpene compounds that are generally present in pinewood emissions. In the PAQ assessment, the percentage of people dissatisfied (PD) with the air quality decreased with increased ventilation in all studied buildings. However, at the lowest and highest ventilation, the pinewood building had the second-lowest PD despite higher VOC levels. The findings of this study can be utilized in interpreting the effects of ventilation design and material selection on IAQ in low-energy buildings.
The main objective of this study is to assess the impacts of cooking and indoor air quality (IAQ) in the southwestern region of Bangladesh. Here we report and compare the IAQ in considering a total of eight kitchens and living rooms of four selected households (HHs) in Jashore city and suburb area, the southwest district of Bangladesh. Air quality parameters, such as particulate matter (PM 2.5) and volatile organic compounds (VOC), were assessed continuously for 24 hours. In addition, Carbon dioxide (CO 2) was evaluated in different phases during the study period. PM 2.5 , VOC, and CO 2 levels were ranged from 18.52-207µg/m3 , 7.95-35.66 ppm, and 1061-2459 mg/m 3 , respectively, in the indoor cooking HHs. Conversely, while the average concentration was found between 20.63-23.72 µg/m3 PM 2.5 , 11.18 9-12.36 ppm VOC, and 1097-1747 mg/m 3 CO 2 in the outdoor cooking HHs. A significant increase in CO 2 due to kitchen activities (cooking, frying, boiling) was observed that ranged between 5-77% 11 compared to the background level. The calculated range of toxicity potential (TP) values was between 12 0.8 to 8.3 for PM 2.5 in the HHs. In most of the observations, PM 2.5 , VOC, and CO 2 exceed the standard values. The study reports that well ventilation systems and clean fuel use significantly reduce the indoor air contaminants level. Our study offers new insights about the IAQ of the southwest region of Bangladesh, particularly for suburbs and urban setups, and provides a background for further study, and decision-making. It will serve as a reference for the formulation and implementation of policies to improve air quality.
We performed a cross‐sectional survey of 2143 female students in a university in Tianjin, China regarding perceived air quality (PAQ) and sick building syndrome (SBS) symptoms in the student dormitory. The prevalence of general, mucosal, and skin symptoms was 22.1%, 21.9%, and 26.3%, respectively. The three most prevalent PAQ complaints were “dry air” (48.9% often), “stuffy odor” (18.2%), and “other unpleasant odors” (5.1%), and they were significant risk factors for 11–12 out of 12 SBS symptoms (adjusted odds ratios [AOR]: 1.6–5.8). Survey data of 1471 undergraduates, whose dorms were of uniform layout and furnishing, were used to further investigate the influences of occupancy level and occupant behaviors on PAQ and SBS symptoms. Frequent use of air freshener/perfume was a significant risk factor for “dry air,” less frequent room cleaning and higher occupancy density were significant risk factors for “stuffy odor,” and less natural ventilation was a significant risk factor for both “stuffy odor” and “pungent odor.” These factors were also significantly associated with some SBS symptoms. In particular, the use of air freshener/perfume exhibited a significant dose–response pattern with “fatigue” (sometimes: AOR 1.3; often: AOR 2.0) and with “irritated, stuffy, or runny nose” (sometimes: AOR 1.6; often: AOR 2.2).
Ventilation system performance in high‐rise multi‐unit residential buildings (MURBs) has a significant impact on resident wellbeing. While the importance of ventilation is well established, it is commonly overlooked since underperformance often goes undetected. This article presents a review and synthesis of ventilation system performance in high‐rise MURBs located in cold climates as it relates to the three pillars of sustainability: economic (capital and operational cost), social (airflow control, indoor environmental quality, and occupant behavior and interactions), and ecological (energy and carbon). A meta‐analysis revealed previous ventilation system designs generally prioritized economic sustainability, specifically, capital cost. However, priorities have recently shifted toward social and ecological sustainability. While this shift is positive, there is insufficient empirical evidence showing which ventilation system most effectively supports it. The decentralized heat/energy recovery ventilator (HRV/ERV) system shows the potential to improve upon the social and ecological sustainability of previous designs, such as the centralized pressurized corridor system, but the interconnected nature of performance metrics can cause improvements to one to negatively impact others. Therefore, further research is required to enhance ventilation system performance in cold climate, high‐rise MURBs, and facilitate decision‐making while designing and retrofitting these systems.
This article maps the socio-technical interconnections between atmospheric systems, on the one hand, and the infrastructural networks associated with the extraction, production, transport and consumption of energy resources, on the other hand. The exchanges, interdependencies and injustices that arise at this interface can broadly be understood as the ‘air–energy nexus’. Despite energy inequalities almost always being entangled with some form of atmospheric injustice, their intersection has rarely been articulated to date. With the aid of a critical literature review, we focus on the domestic air–energy nexus to explore the ability of air to act as a social and physical agent of deprivation and injustice in the case of energy vulnerability: a condition characterized by a household’s propensity to secure adequate levels of energy services in the home. We argue that an integrated and critical perspective on the air–energy nexus challenges existing understandings of the quality and nature of domestic energy and atmospheric services, such as space heating and cooling. We propose future research and policy directions focused on addressing energy vulnerability in the home by embracing the unruly and fluid character of air–energy interactions, and transcending the socio-material boundaries between indoor and outdoor environments.
Due to the majority of time people spent indoors, indoor air quality is not only critical to people's health, comfort, but can also significantly influence occupants perception on indoor environment. Air quality is closely related to many factors including thermal parameters, pollutant concentrations, and ventilation performance. However, the current building indoor air quality evaluation method is based the objective measurement of indoor parameters, without considering occupants’ subjective perception. This paper is aimed at summarizing a profound review on the PAQ evaluation method. Comparisons among various PAQ evaluating methods with advantages, similarities and differences were conducted. Analysis of literatures about indoor air quality in Chinese residential buildings field is also summarized, and discussion on the subjective influence of temperature and relative humidity, ventilation performance, volatile organic compounds (VOCs) concentration, and particulate matters on perceived air quality is carried out.
Application of Engineering and Technology in Bridging Technology and Community
With a modified version of the Wells-Riley model, we simulated the size distribution and dynamics of five airborne viruses (measles, influenza, SARS-CoV-2, human rhinovirus, and adenovirus) emitted from a speaking person in a typical residential setting over a relative humidity (RH) range of 20–80% and air temperature of 20–25 °C. Besides the size transformation of virus-containing droplets due to evaporation, respiratory absorption, and then removal by gravitational settling, the modified model also considered the removal mechanism by ventilation. The trend and magnitude of RH impact depended on the respiratory virus. For rhinovirus and adenovirus humidifying the indoor air from 20/30 to 50% will be increasing the relative infection risk, however, this relative infection risk increase will be negligible for rhinovirus and weak for adenovirus. Humidification will have a potential benefit in decreasing the infection risk only for influenza when there is a large infection risk decrease for humidifying from 20 to 50%. Regardless of the dry solution composition, humidification will overall increase the infection risk via long-range airborne transmission of SARS-CoV-2. Compared to humidification at a constant ventilation rate, increasing the ventilation rate to moderate levels 0.5 → 2.0 h⁻¹ will have a more beneficial infection risk decrease for all viruses except for influenza. Increasing the ventilation rate from low values of 0.5 h⁻¹ to higher levels of 6 h⁻¹ will have a dominating effect on reducing the infection risk regardless of virus type.
Background: Photocatalytic air purifiers based on nano-titanium dioxide (TiO 2 ) visible light activation provide an efficient solution for removing and degrading contaminants in air. The potential detachment of TiO 2 particles from the air purifier to indoor air could cause a safety concern. A TiO 2 release potential was measured for one commercially available photocatalytic air purifier “Gearbox Wivactive” to ensure a successful implementation of the photocatalytic air purifying technology.
Methods: In this study, the TiO 2 release was studied under laboratory-simulated conditions from a Gearbox Wivactive consisting of ceramic honeycombs coated with photocatalytic nitrogen doped TiO 2 particles. The TiO 2 particle release factor was measured in scalable units according to the photoactive surface area and volume flow (TiO 2 -ng/m ² ×m ³ ). The impact of Gearbox Wivactive on indoor concentration level under reasonable worst-case conditions was predicted by using the release factor and a well-mixed indoor aerosol model.
Results: The instrumentation and experimental setup was not sufficiently sensitive to quantify the emissions from the photoactive surfaces. The upper limit for TiO 2 mass release was <185×10 ⁻³ TiO 2 -ng/m ² ×m ³ . Under realistic conditions the TiO 2 concentration level in a 20 m ³ room ventilated at rate of 0.5 1/h and containing two Gearbox Wivactive units resulted <20×10 ⁻³ TiO 2 -ng/m ³ .
Conclusions: The release potential was quantified for a photocatalytic surface in generalized units that can be used to calculate the emission potential for different photocatalytic surfaces used in various operational conditions. This study shows that the TiO 2 nanoparticle release potential was low in this case and the release does not cause relevant exposure as compared to proposed occupational exposure limit values for nanosized TiO 2 . The TiO 2 release risk was adequately controlled under reasonable worst-case operational conditions.
A shading device is integrated into a building in reducing the indoor solar heat gained. However, the incorporation of a shading device into an opening provides certain effects on indoor natural ventilation. Its performance in enhancing the indoor airflow is still arguable. For this reason, a comprehensive review was executed to identify the effects of a shading device on the natural ventilation of a building. A schematic review process was executed to identify the published articles that were related to the shading devices at the building openings. Subsequently, 25 articles have examined the shading devices at the building openings. The output parameters that were discussed including, the solar heat gained, temperature, energy consumption, daylighting, air quality, airflow, and thermal comfort. The studies agree that the shading device has certain effects on indoor airflow. The effects can be either good or detrimental, depending on the climatic condition, geographical location, building orientation, opening configuration, the shading function, and configuration. It is hoped that this review encourages more investigations of the combined effects of the shading device on solar radiation and natural ventilation. The combined effects are essential in achieving optimum performance of a shading device, which can reduce the solar radiation penetration and enhance the indoor natural ventilation.
Highlights
• This review discusses the application of the shading device in building openings.
• A shading device is categorized based on internal, middle, and external locations.
• A shading device can either enhance or reduce the airflow into the indoor space.
Giorgos Petrou and colleagues argue for systematic large scale monitoring of indoor air to avoid unintended harms to health from home energy efficiency programmes
In most situations, natural ventilation of buildings is not well controlled. Consequently, either insufficient ventilation or over-ventilation is inevitable. However, the use of an automatic and active window requires sensors and driving motors, which entails a non-trivial initial investment and maintenance cost. This investigation proposed a passive, horizontally pivoted window with the sash swinging in the wind for adjustment of the window opening size. The center of gravity of the sash is located above the pivot, while the section of the sash below the pivot is larger than the upper section. Due to the opposing actions of the gravitational torque and the torque created by the blowing wind, the size of the window opening increases or decreases with the wind speed. The above passive pivoted window was constructed and then installed in a laboratory house. The flow rate was measured as a function of the pressure difference. In addition, EnergyPlus modeling was used to simulate an apartment equipped with the passive pivoted windows after validation of the model. The natural ventilation rate, the percentage of time with unacceptable indoor CO2 concentration, and the cooling and heating loads were examined. The performance of the pivoted windows was also compared with that of the traditional regular windows. It was found that the passive pivoted window provided a much more stable natural ventilation rate and better indoor air quality without additional energy consumption. The passive pivoted window has no sensor or motor and thus requires no energy input.
Γεωργίσης, Α., Τσατήρης, Μ., Δήμου Β. 2021. Η ΠΕΡΙΒΑΛΛΟΝΤΙΚΗ ΦΟΡΟΛΟΓΙΚΗ ΜΕΤΑΡΡΥΘΜΙΣΗ-ΦΟΡΟΙ ΕΝΕΡΓΕΙΑΣ ΩΣ ΣΥΓΧΡΟΝΟ ΕΡΓΑΛΕΙΟ ΠΕΡΙΒΑΛΛΟΝΤΙΚΗΣ ΠΟΛΙΤΙΚΗΣ ΚΑΙ Η ΕΦΑΡΜΟΓΗ ΤΗΣ ΣΕ ΧΩΡΕΣ ΤΗΣ ΕΕ. Επιστημονική Επετηρίδα Τμήματος Δασολογίας και Διαχείρισης Περιβάλλοντος και Φυσικών Πόρων. Δημοκρίτειο Πανεπιστήμιο Θράκης. Θέματα Δασολογίας και Διαχείρισης Περιβάλλοντος και Φυσικών Πόρων. 13ος Τόμος: Κλιματική Αλλαγή στην Ανθρωπόκαινο Εποχή, σελ. 32-54.
Cited By (since 1996): 5, Export Date: 4 October 2012, Source: Scopus, Language of Original Document: English, Correspondence Address: Santamouris, M.; Group Building Environmental Studies, Physics Department, University of Athens, Athens, Greece, References: Alevantis, L., Xenaki-Petreas, M., Indoor air quality in practice (1994) 'Energy Conservation in Buildings', , In M Santamouris and DN Assimakopoulos, (Editors), Central Institution Energy Efficiency Education, University of Athens, Athens, Greece;
Phthalates from polyvinyl chloride (PVC) plastics may have adverse effects on airways and immunologic systems, but the evidence has not been reviewed systematically.
We reviewed the evidence for the role of exposure to phthalates from PVC products in the development of asthma and allergies.
We conducted a Medline database search (1950 through May 2007) for relevant studies on the respiratory and allergic effects of exposure to phthalates from PVC products.
We based this review on 27 human and 14 laboratory toxicology studies. Two mouse inhalation experiments indicated that mono-2-ethylhexyl phthalate (MEHP) has the ability to modulate the immune response to exposure to a coallergen. The data suggested a no observed effect level of 30 microg MEHP/m3, calculated to be below the estimated level of human exposure in common environments. Case reports and series (n = 9) identified and verified cases of asthma that were very likely caused by fumes emitted from PVC film. Epidemiologic studies in adults (n = 10), mostly small studies in occupational settings, showed associations between heated PVC fumes and asthma and respiratory symptoms; studies in children (n = 5) showed an association between PVC surface materials in the home and the risk of asthma [fixed-effects model: summary odds ratio (OR), 1.55; 95% confidence interval (CI), 1.18-2.05; four studies] and allergies (OR, 1.32; 95% CI, 1.09-1.60; three studies).
High levels of phthalates from PVC products can modulate the murine immune response to a coallergen. Heated PVC fumes possibly contribute to development of asthma in adults. Epidemiologic studies in children show associations between indicators of phthalate exposure in the home and risk of asthma and allergies. The lack of objective exposure information limits the epidemiologic data.
Unlabelled:
In a nested case-control study with 198 children with asthmatic and allergic symptoms (cases) and 202 healthy controls in Värmland, Sweden, we have investigated the relationship between mold spore exposure (mean colony-forming unit) indoor and (i) different indexes of moldy odor indoor (observed by professional inspectors and reported by parents), (ii) visible signs of dampness in the homes of the children (observed and reported), and (iii) doctor-diagnosed asthma/allergy in children. No association was found between the spore concentration indoor and moldy odor and signs of visible dampness in the homes. When a semi-quantitative method in distinguishing between moldy houses or non-moldy houses was used, there were no significant differences between the observed indexes of moldy odor or visible signs of dampness (both observed and reported). No association could be found between the spore concentration in indoor air and asthma/allergy in the children.
Practical implications:
Mold spore exposure indoor have been suggested as a possible explanation for airway problems such as asthma and allergy among people living in buildings with moisture-related problems. However, this investigation could not find any associations between the spore concentrations in indoor air and signs of dampness and moldy odor reported by parents or observed by professional inspectors. Neither was there any association between the indoor spore concentration and asthma/allergy among children. With these results, there is no reason for one-time air sampling of mold colony-forming unit (CFU) in indoor air of homes to identify risk factors for asthma/allergy in children living in Scandinavian countries.
The aim of this review was to assess the evidence from recent prospective studies that long-term traffic pollution could contribute to the development of asthma-like symptoms and allergic sensitization in children. We have reviewed cohort studies published since 2002 and found in PubMed in Oct 2008. In all, 13 papers based on data from 9 cohorts have evaluated the relationship between traffic exposure and respiratory health. All surveys reported associations with at least some of the studied respiratory symptoms. The outcome varied, however, according to the age of the child. Nevertheless, the consistency in the results indicates that traffic exhaust contributes to the development of respiratory symptoms in healthy children. Potential effects of traffic exhaust on the development of allergic sensitization were only assessed in the four European birth cohorts. Long-term exposure to outdoor air pollutants had no association with sensitization in ten-year-old schoolchildren in Norway. In contrast, German, Dutch and Swedish preschool children had an increased risk of sensitization related to traffic exhaust despite fairly similar levels of outdoor air pollution as in Norway. Traffic-related effects on sensitization could be restricted to individuals with a specific genetic polymorphism. Assessment of gene-environment interactions on sensitization has so far only been carried out in a subgroup of the Swedish birth cohort. Further genetic association studies are required and may identify individuals vulnerable to adverse effects from traffic-related pollutants. Future studies should also evaluate effects of traffic exhaust on the development and long term outcome of different phenotypes of asthma and wheezing symptoms.
It is unclear whether asthma is overdiagnosed in developed countries, particularly among obese individuals, who may be more likely than nonobese people to experience dyspnea.
We conducted a longitudinal study involving nonobese (body mass index 20-25) and obese (body mass index >/= 30) individuals with asthma that had been diagnosed by a physician. Participants were recruited from 8 Canadian cities by means of random-digit dialing. A diagnosis of current asthma was excluded in those who did not have evidence of acute worsening of asthma symptoms, reversible airflow obstruction or bronchial hyperresponsiveness, despite being weaned off asthma medications. We stopped asthma medications in those in whom a diagnosis of asthma was excluded and assessed their clinical outcomes over 6 months.
Of 540 individuals with physician-diagnosed asthma who participated in the study, 496 (242 obese and 254 nonobese) could be conclusively assessed for a diagnosis of asthma. Asthma was ultimately excluded in 31.8% (95% confidence interval [CI] 26.3%-37.9%) in the obese group and in 28.7% (95% CI 23.5%-34.6%) in the nonobese group. Overdiagnosis of asthma was no more likely to occur among obese individuals than among nonobese individuals (p = 0.46). Of those in whom asthma was excluded, 65.5% did not need to take asthma medication or seek health care services because of asthma symptoms during a 6-month follow-up period.
About one-third of obese and nonobese individuals with physician-diagnosed asthma did not have asthma when objectively assessed. This finding suggests that, in developed countries such as Canada, asthma is overdiagnosed.
Because of the energy saving constructions and the use of pollutants containing construction materials is the natural air exchange rate of new or redecorated buildings often underneath 0.5 h-1 which is to low from the hygienic point of view. It is demanded an air exchange rate between 0.8 h-1 and 1 h-1 in used rooms. We are giving an overview about air exchanging rates and we are presenting a method for measuring air exchange rates which we further developed. Through a thermostabilisated tracergas source the tracergas is emitting continuously into the room. The evaluation is made by GC/ECD. It is possible to detect air exchange rates until 0.01 h-1. Some results from our institute are presented too.
When interpreting seasonal variations of indoor concentrations of volatile organic compounds (VOC), the ventilation rate must be known. Therefore, a method has been developed which permits the simultaneous determination of the average ventilation rate and the concentration of VOC in a room over an integration period of two week with the same passive sampler. Hexafluorobenzene (HFB), a non-toxic substance, was chosen as the tracer so as not to interfere in the gas chromatographic analysis of VOC in indoor air. Emission rates of HFB sources were determined at various temperatures from 15 to 30°C. After a test of the procedure for sampling periods of one and two weeks in an experimental chamber at ventilation rates between 0.5 and 2 hâ»Â¹, the procedure was successfully applied under field conditions. Good agreement was obtained when comparing the HFB method with a perfluorocarbon technique.
Knowledge of the occurrence of volatile organic compounds (VOC) in indoor air has been steadily increasing during the last few years. However, information about the extent of the variation of VOC concentrations due to changing seasonal conditions has remained scarce. To fill this gap, VOC concentrations in 12 households in Berlin were followed over one year by exposing passive samplers for 26 two-week periods each. The analysis of VOC included determinations of alkanes, aromatics, halocarbons, and polar compounds. Smokers' and nonsmokers' homes in old and new buildings were chosen for the study. For each sampling period, the test families listed activities and the use of products susceptible to emit VOC. In one part of the study, VOC determinations were completed by measurements of the ventilation rate. In most of the households, the total VOC concentration level in winter was about two to three times higher than in summer. The compounds emanating from intermittent sources could in part be assigned to the activities of the occupants.
HOPE (Health Optimisation Protocol for Energy-efficient Buildings) was a collaborative European project, which aimed to demonstrate that energy-efficient buildings can be both healthy and comfortable for their occupants. The fieldwork within the HOPE project included a preliminary cross-sectional stage using building checklists and occupant questionnaires, and a more detailed investigation of a small number of home and office buildings. These measurements aimed to evaluate indoor environmental quality (including ventilation). The main problems found in the UK offices were related to ventilation, high temperature and high levels of particulate matter, areas that were also highlighted as concerns in the occupant questionnaires. This means that perceived occupant health may be a preliminary indication for office building evaluation. However, that was not the case in the UK homes, where occupant health and comfort were not consistent with physical environmental measurements, indicating that perceived health and comfort was based on more than the physical parameters and cannot be fully explained by the measurements.
In this study we estimate the air leakage distribution of single-family dwellings in Catalonia and use a statistical analysis of an airtightness database for single-family dwellings in France to identify the building characteristics that have the greatest influence on airtightness. The most significant variables are found to be the structure type, the floor area, the age of the building, the number of stories and the insulation type. A multiple linear regression technique is then applied to establish a predictive model for deriving an estimated value of airtightness from these characteristics. To estimate the infiltration airflow, a stochastic simulation of the building characteristics was performed per census tract using real data on the distributions of building variables taken from the census information. The model is then applied to determine the power law coefficient and the airtightness distribution. The predicted flow coefficients are combined with the AIM-2 model and given meteorological conditions to determine the infiltration airflow. Two sets of meteorological conditions are considered: average conditions and extreme conditions for each season.
In this study, we performed a series of trials to measure the infiltration air exchange rate (ACH) of several single-family dwellings throughout Catalonia, as well as the ACH of sealed rooms that could be used as indoor shelters. A shelter is an indoor room where people can take protection in case of a toxic gas release, while the toxic cloud passes through the dwelling. Experimental measurements were made using the tracer gas decay technique with CO2 as the tracer gas in 2 periods—summer and winter—with the aim of characterizing air infiltration in Catalan dwellings. The geometric means obtained for the ACH of shelters and dwellings were 0.16 and 0.23h−1, respectively, that is, lower than those reported for North American (0.56h−1) and Greek (0.76h−1) dwellings. In general, the ACH was lower for shelters than for dwellings, and the average reduction obtained in shelters with respect to dwellings was 35%. The largest reductions were obtained in old dwellings with small floor areas and few stories. As for meteorological conditions, we found that the ACH of dwellings was more closely linked to wind speed than indoor–outdoor temperature difference, while the ACH of shelters was more affected by indoor–outdoor temperature and temperature differences inside the dwelling, particularly in dwellings with 3 or more stories.
Conference code: 88515, Export Date: 4 October 2012, Source: Scopus, Language of Original Document: English, Correspondence Address: Santamouris, M.; University Athens, Panepistimioupolis, Athens, Greece; email: msantam@phys.uoa.gr, References: Franchi, M., Carrer, P., Kotzias, D., Rameckers, E.M.A.L., Seppanen, O., Van Bronswijk, J.E.M.H., Viegi, G., Valovirta, E., Working towards healthy air in dwellings in Europe (2006) Allergy: European Journal of Allergy and Clinical Immunology, 61 (7), pp. 864-868. , DOI 10.1111/j.1398-9995.2006.01106.x;, Sponsors: Air Infiltration and Ventilation Centre (AIVC)
Cited By (since 1996): 12, Export Date: 4 October 2012, Source: Scopus, CODEN: BUEND, doi: 10.1016/j.buildenv.2007.01.006, Language of Original Document: English, Correspondence Address: Sfakianaki, A.; Department of Applied Physics, Physics Department, National and Kapodistrian University of Athens, Group Bldg. Environmental Research, Bldg. Physics 5, 15784 Athens, Greece, References: Sherman, M.H., Dickerhoff, D., Air tightness of US dwellings (1998) ASHRAE Transactions, 104 (2), pp. 1359-1367;
Air change rate (ACR) data obtained from the bedrooms of 500 Danish children and presented in an earlier paper were analyzed in more detail. Questionnaires distributed to the families, home inspections and interviews with the parents provided information about a broad range of residential characteristics and occupant behavior. These were tested in several linear regression models to identify the degree of effect each selected independent variable has on the total ACR. The measured ACRs are summarized by some of the most significant variables such as room volume (higher ACR in smaller rooms), number of people sleeping in the bedroom (higher ACR with more people), average window and door opening habits (higher ACR with more opening), sharing the bedroom with other family members (higher ACR in shared rooms), location of the measured room (higher ACR above ground floor), year of construction (lowest ACR in buildings from early 1970s), observed condensation on the bedroom window (higher ACR at less condensation), etc. The best-fitting model explained 46% of the variability in the air change rates. Variables related to occupant behavior were stronger predictors of ventilation rate (model R2 = 0.30) than those related to building characteristics (model R2 = 0.09). Although not perfectly accurate on a room-to-room basis, our best-fitting model may be useful when a rough estimate of the average air change rate for larger study populations is required in future indoor air quality models.
Abstract To investigate the effect of ventilation on indoor radon (222Rn), simultaneous measurements of radon concentrations and air change rates were made in 117 Danish naturally ventilated slab-on-grade houses built during the period 1984–1989. Radon measurements (based on CR-39 alpha-track detectors) and air change rate measurements (based on the perfluorocarbon tracer technique; PFT) were in the ranges 12–620 Bq m−3 and 0.16−0.96 h−1, respectively. Estimates of radon entry rates on the basis of such time-averaged results are presented and the associated uncertainty is discussed. It was found that differences in radon concentrations from one house to another are primarily caused by differences in radon entry rates whereas differences in air change rates are much less important (accounting for only 80,0% of the house-to-house variation). In spite of the large house-to-house variability of radon entry rates it was demonstrated, however, that natural ventilation does have a significant effect on the indoor radon concentration. Most importantly, it was found that the group of houses with an air change rate above the required level of 0.5 h−1 on average had an indoor radon concentration that was only 50% (0.5±0.1) of that of the group of houses with air change rates below 0.5 h−1. The reducing effect of increased natural ventilation on the indoor radon concentration was found to be due mainly to dilution of indoor air. No effect could be seen regarding reduced radon entry rates.
The indoor air quality in several types of dwellings that were renovated to save energy for spatial heating has been investigated. Concentrations of pollutants were monitored in three rooms of inhabited houses. Data of the outside air and ventilation and infiltration were also collected. Relationships were established between observed concentrations and ventilation. In some cases concentrations show a good relationship with the calculated air change rate, in other cases this relationship was poor or absent.Elevated levels of pollutants could be related to sources in most cases. The ventilation behavior of the inhabitants has a major influence on the concentrations.From this and other studies it can be concluded that, in general, making dwellings more airtight leads to higher concentrations of pollutants. Deviations from health-related guidelines then become more likely.
The purpose of the study was to gather information about the actual ventilation and indoor air quality and to evaluate the differences between houses and apartments with different ventilation systems. A sample of 242 dwellings in the Helsinki metropolitan area was studied over periods of no weeks during the 1988-1989 heating season. The mean air-exchange rates had a high variation (average 0.52 l/h, range 0.07-1.55 l/h). The ASHRAE minimum value of 0.35 l/h was not achieved in 28% of the dwellings. The air-exchange rates were significantly her in the houses than in the apartments (averages 0.45/0.64 l/h, p < 0.001); in the natural ventilation systems they, were slightly her than in the mechanical systems. The average temperature in the bedrooms was approximately 22 °C (range 18–27 °C), slightly but significantly higher in the apartment than in the houses. The average dust depositions were higher in the balanced ventilation systems than in the other systems. The median radon concentration was 82 Bq/m3 (range 5-866 Bq/m3); the Finnish target value of 200 Bq/m3 was exceeded in 17% of the houses but in none of the apartment. The measurements indicate that the indoor air quality in Finnish dwellings is not always satisfactory with reference to human health and comfort.
Abstract The ventilation in Norwegian residences was studied with respect to the effect of new standards, construction techniques adopted, and energy conservation measures implemented. This was compared to residential ventilation performance in other countries with a similar climate. The effective total air change rate (h−1) in 344 residences was measured with a passive tracer gas method known as the perfluorocarbon tracer gas method (PFT-method). The measurements were performed over a 14-day integrated sampling period. Overall, 36% of all residences had lower air change rates than the national building code requirement of 0.5 h−1. In spite of similar construction techniques and building codes in the Nordic countries, Norwegian residences seem to be better ventilated in general than residences in other Nordic countries. However, the common belief of a gradual reduction of ventilation rates in Norwegian buildings as the date of construction becomes more recent is supported by our findings which show a linear reduction (slope β=−0.002, P < 0.05) of ventilation until the revision of the national building codes in 1987. Consequently, our results provide evidence supporting the hypothesis that the introduction of new building standards and construction techniques, and the implementation of energy conservation measures, have decreased the effective total air change rates in Norwegian residences until 1987.
Background: An IgE-mediated contact reaction to airborne allergens has been suggested as one important pathogenetic mechanism in atopic dermatitis (AD). The house-dust mite (HDM) might be a common allergen involved. In Scandinavia, sensitization to HDM has been rare, probably because of the cold, dry climate. However, recent studies indicate high levels of domestic mites and HDM allergen in 15–20% of homes in central and northern Sweden.
Methods: To evaluate the importance of the HDM in patients with AD in the Stockholm region, we screened 81 adult Stockholm residents with AD, for the prevalence and degree of sensitization to the HDM, according to specific IgE (RAST), skin prick test (SPT), and atopy patch test (APT). We also assessed the HDM exposure in their homes and correlated the results with clinical history, severity of the dermatitis, and type of residence during childhood and today.
Results: The sensitization rate to HDM was high (56% according to RAST, 24% according to SPT, and 47% according to APT), and 20% of the patients were exposed to HDM allergens in their beds. Mite exposure seemed to aggravate the dermatitis in highly sensitized patients.
Conclusions: The results indicate that we have to take the HDM into account when discussing aggravating factors in adult patients with AD in the Stockholm region.
The purpose of the study was to evaluate the occurrence of symptoms and the perception of poor indoor air quality among the occupants of houses and apartments with different ventilation systems. The study population consisted of the 473 occupants of 242 dwellings in the Helsinki metropolitan area who responded to a self-administered questionnaire (response rate 93.1%) after a two-week period of indoor air quality measurements. The symptoms of interest were those often related to poor indoor air quality including dryness or itching of the skin; dryness, irritation or itching of the eyes; nasal congestion (“blocked nose”) nasal dry-ness; nasal discharge (“runny nose”); sneezing; cough; breathlessness; headache or migraine; and lethargy, weakness or nausea. Perception of coldness; warm-ness; draught; dryness; stuffiness; and sufficiency of air exchange was also requested. The age-standardized period prevalences of the symptoms and complaints were systematically more common among the occupants of the apartments than those of the houses. The occupants of the houses with natural ventilation seemed to have more symptoms and complaints than those with balanced ventilation. However, in the apartments with balanced ventilation the occupants reported, in general, more symptoms and complaints than those with natural ventilation.
Buildings complying with the Passive House standard are rapidly spreading across Germany, Austria and Switzerland. The underlying Passive House concept is based on a holistic approach, improving the building envelope to a degree that allows for substantial simplifications of the heating system. Passive Houses offer increased comfort at affordable costs while significantly reducing the energy consumption. The useful energy required for space heating has been reduced by ca. 80% compared with conventional (new) buildings. The overall primary energy consumption (including all services and electric appliances) has been reduced by more than 50%. Our paper introduces the Passive House standard and summarizes results of the EU project ‘Cost Efficient Passive Houses as European Standards’ (CEPHEUS) with respect to energy indices and comfort. Characteristics of the combined ventilation and heating system realized in many Passive Houses are presented in detail, including results of an expert working group at the Passive House Institute and on measurements and simulations conducted at EMPA. Chances and limitations of wood stoves as supplementary heat sources in Passive Houses are discussed shortly.
A passive tracer gas method is applied to measure ventilation rates in a nation-wide indoor climate study of a statistical sample of the Swedish housing stock. The method and experimental design are described, together with the results and some experiences gained from the project. The evaluation and error analysis techniques are discussed from an example. Special attention is paid to the accuracy of the results and the probable causes and size of errors. It is shown that the ventilation flow rates could be estimated to an acceptable degree of accuracy. Distributions of ventilation rates in single- and multi-family buildings are presented and discussed. It is shown that actual ventilation rates in dwelling are generally low compared to the requirements in Sweden since 1975, especially in single-family houses. The average ventilation rate per occupant is however very similar in multi- and single-family buildings.
The ongoing “Indoor Environment and Children’s Health” (IECH) study investigates the environmental risk factors in homes and their association with asthma and allergy among children aged 1–5 years. As part of the study, the homes of 500 children between 3 and 5 years of age were inspected. The selected children included 200 symptomatic children (cases) and 300 randomly selected children (bases). As part of the inspection, the concentration of carbon dioxide in the bedrooms of the children was continuously measured over an average of 2.5 days. The ventilation rates in the rooms during the nights when the children were sleeping in the room were calculated using a single-zone mass balance for the occupant-generated CO2. The calculated air change rates were log-normally distributed (R2 > 0.98). The geometric mean of the air change rates in both the case and the base group was 0.46 air changes per hour (h−1; geom. SD = 2.08 and 2.13, respectively). Approximately 57% of both cases and bases slept at a lower ventilation rate than the minimum required ventilation rate of 0.5 h−1 in new Danish dwellings. Only 32% of the bedrooms had an average CO2 concentration below 1000 ppm during the measured nights. Twenty-three percent of the rooms experienced at least a 20-minute period during the night when the CO2 concentration was above 2000 ppm and 6% of the rooms experienced concentrations above 3000 ppm. The average air change rate was higher with more people sleeping in the room. The air change rate did not change with the increasing outdoor temperature over the 10-week experimental period. The calculation method provides an estimate of the total airflow into the bedroom, including airflows both from outdoors and from adjacent spaces. To study the accuracy of the calculated air change rates and their deviation from the true outside air change rates, we calculated CO2 concentrations at different given air change rates using an indoor air quality and ventilation model (Contam). Subsequently we applied our calculation procedure to the obtained data. The air change rate calculated from the generated CO2 concentrations was found to be between 0% and 51% lower than the total air change rate defined in the input variables for the model. It was, however, higher than the true outside air change rate. The relative error depended on the position of the room in relation to the adjacent rooms, occupancy in the adjacent room, the nominal air change rate and room-to-room airflows.
The present study has been conducted in the frame of BUMA (Prioritization of Building Materials Emissions as indoor pollution sources), a European funded project, aiming at assessing the exposure to emitted compounds in indoor air. Field campaigns in five (5) European cities (Milan, Copenhagen, Dublin, Athens and Nicosia) were carried out. These campaigns covered weekly winter and summer concentration measurements in two (2) public buildings and two (2) private houses in each city. BTEX, terpenes, and carbonyls were measured using passive sampling in two sites inside the building and one outside. VOC emission measurements on selected building material have also been performed using Field and Laboratory Emission Cell (FLEC). The results on indoor concentrations for compounds such as formaldehyde (1.2–62.6 μg m−3), acetaldehyde (0.7–41.6 μg m−3), toluene (0.9–163.5 μg m−3), xylenes (0.2–177.5 μg m−3) and acetone (2.8–308.8 μg m−3) have shown diversity and relatively significant indoor sources depending on the building type, age etc. Indoor concentrations of these substances are varied depending on the building age and type. The percentage of approximately 40% of the indoor air quality levels originated from building materials.