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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Characterization of Vehicular Exhaust Emissions and Indoor Air Quality of Public Transport Buses Operating on Alternative Diesel Fuels

Vijayan, Abhilash January 2007 (has links)
No description available.
82

<b>Analyses of Static and Dynamic Airflow and </b><b>Contaminant Dispersion in Elevator Environments</b>

Chengbo Du (20325909) 10 January 2025 (has links)
<p dir="ltr">This study investigates airflow patterns and contaminant concentration in elevator-related areas, highlighting their critical role in indoor air quality and infection control. Despite widespread reliance on elevators, limited research addresses airflow patterns and contaminant behavior in these confined, high-density spaces. Using a full-scale elevator mockup connected to a lobby, this study conducted static and dynamic experiments to measure air velocity, temperature, and contaminant concentration. Static tests analyzed closed cabins with mixed ventilation, while dynamic tests examined the impact of passenger movement on airflow and contaminant dispersion.</p><p dir="ltr">Experimental data validated a Computational Fluid Dynamics (CFD) model, which revealed relatively uniform air conditions during elevator transit and notable wake effects associated with passenger movement. The CFD model simulated scenarios involving an index patient engaging in various respiratory activities, such as talking and coughing. Results showed that while the infection risk during short elevator rides is generally low, proximity to an infected individual during activities like talking increases transmission risk.</p><p dir="ltr">The findings underscore CFD’s value in studying both static and dynamic indoor airflow, though complexities in dynamic cases necessitate refined models and experimental methods. Additionally, the study enhances traditional displacement ventilation systems with induction panels and emphasizes the importance of integrated design for elevators and adjacent spaces to optimize ventilation performance and reduce infection risks during airborne crises, such as pandemics. This research advances understanding of indoor air quality in confined environments, providing insights for safer and more effective ventilation design.</p>
83

Toxiska luftföroreningar ombord på fartyg : Riskbedömning av svensk ombordpersonals yrkesmässiga exponering för toxiska luftföroreningar

Andersson, Caroline, Eklund, Henrik January 2016 (has links)
Syftet med arbetet var att samla in mätdata för att kontrollera luftkvalitén ombord på två svenska fartyg, för att sedan jämföra resultaten med Arbetsmiljöverkets hygieniska gränsvärden och den svenska normalbefolkningens exponering för olika ämnen. Resultatet från studien var också tänkt att vara till hjälp för att utforma nya råd och rekommendationer för att minimera exponeringen och även till att bidra med material för fler framtida studier. Under cirka en vecka ombord på fartygen samlades data in med hjälp av passiva provtagare för att registrera halter av bensen, kvävedioxid och polycykliska aromatiska kolväten. Resultaten visade att luftkvalitén ombord på de två fartygen generellt sett är god. Samtliga uppmätta halter låg långt under Arbetsmiljöverkets gränsvärden och det skiljde sig inte mycket varken mellan fartyg eller jämfört med den svenska normalbefolkningens exponering. Därför är inte svensk sjömän ombord på svenskflaggade fartyg i större fara för toxiska luftföroreningar ombord jämfört med när de är hemma. / The main purpose of this study was to measure and evaluate the air quality onboard two Swedish ships, and compare the results with the exposure limits laid out by the Swedish Work Environment Authority (Arbetsmiljöverket) and the Swedish population’s exposure to various substances. The results of this study were also meant to be helpful to form new advice and recommendations to minimize exposure and also to provide material for future studies. During approximately one week onboard the two ships data were collected using passive samplers to register levels of benzene, nitrogen dioxide and polycyclic aromatic hydrocarbons. The results indicated that the air quality onboard the two ships were generally good. All measured concentrations were well below safety applications and it did not differ very much neither between ships nor compared with the Swedish population’s exposure. In conclusion, Swedish sailors onboard Swedish ships are not in greater danger of toxic air pollutants onboard compared to when they are at home.
84

Assessment of the indoor air quality at the corporate offices of a South African mining company / Marius Meintjes

Meintjes, Marius January 2013 (has links)
Abstract: The aim of the study was to evaluate the indoor air quality (IAQ) of a semi-airtight (the building only utilises mechanical means to ventilate the occupied spaces however an airtight seal is not established as a result of infiltration due to building design) office building that is situated in central Johannesburg that exclusively uses a heating, ventilation and air-conditioning (HVAC) system for ventilation. This implies a system that only utilises mechanical ventilation to heat, cool, humidify and clean the air for comfort, safety and health of employees. This includes the control of odour levels, and also the maintenance of carbon dioxide (CO2) below stipulated levels. Methods: The building is divided into two sections; west and east. Each section has its own ventilation supply. A randomisation process was used to ascertain which offices needed to be sampled, in which section as well as on which floor. For this study, five offices per section were measured. Thus, ten offices per floor were measured and measurements were taken on every second floor. All measurements were done in accordance with the specific requirements of the manufacturer of any specific instrument used and measurements were taken over an eight hour period (full work shift). Results were compared to the available standard, as well as compared to the ambient concentrations. Results: None of the monitored contaminants’ concentration were above the provided standards (ASHRAE or ACGIH). Where standards were unavailable, the HVAC system maintained an indoor contaminant concentration that is substantially lower when compared to the outdoor air concentrations. Conclusion: The buildings’ HVAC system maintains indoor air quality at a healthy level it is unlikely that any one of these contaminants may lead to SBS amongst the employees. / MSc (Occupational Hygiene), North-West University, Potchefstroom Campus, 2014
85

Caractérisation du comportement des aérosols microbiens dans les réseaux de ventilation d'espaces occupés / Microbial aerosol behavior in HVAC system

Forthomme, Audrey 18 December 2012 (has links)
La qualité microbienne de l’air intérieur représente un enjeu sanitaire important, notamment dans le secteur professionnel. Ces travaux de thèse ont permis d’étudier les conditions favorisant le développement des espèces microbiennes collectées sur des médias fibreux utilisés dans des CTA, ainsi que leur réentrainement an aval de la filtration, susceptible de dégrader la qualité de l’air. La première partie de l’étude s’est déroulée en laboratoire à partir de la filtration d’un consortium bactérien – fongique composé de Staphylococcus epidermidis et Penicillium oxalicum. L’influence de trois paramètres a été étudiée sur la croissance microbienne : le taux d’humidité relative (HR) de l’air, la nature du média fibreux, la présence/absence de flux d’air. Les résultats ont révélé notamment que quelles que soient les conditions,S. epidermidis n’arrive pas à croître. En revanche, lorsque l’HR de l’air approche 100%, P. oxalicum se développe sur les filtres et des spores sont relarguées en aval des filtres après une reprise de la filtration. Une seconde partie de l’étude a consisté à travailler avec un aérosol atmosphérique semi urbain. Deux unités de filtration d’air ont fonctionné pendant 5 mois en parallèle. La ventilation d’une des deux unités a été stoppée chaque week-end et redémarrée en début de semaine. Un suivi de la température, de l’humidité de l’air, de la perte de charge des filtres et de la concentration des particules totales dans l’air en amont de la filtration a été assuré tout au long de l’étude. Les concentrations en microorganismes cultivables ont été mesurées chaque semaine en amont et en aval de chaque filtre, notamment au redémarrage de la ventilation. En fonction des variations saisonnières de la concentration des microorganismes, les résultats ont montré en particulier des efficacités de filtration vis-à-vis des particules bactériennes faibles, voire négatives, dans l’unité de filtration fonctionnant en continu. / Microbial indoor air quality is an important issue in particular in the professional sector. This thesis aims to investigate the conditions leading to microbial development on to fibrous filters and to microbial release down stream of filters that could decrease air quality. The first part of the thesis was realized on laboratory and consisted in the filtration of a microbial consortium composed with Staphylococcus epidermidis (bacterium specie) and Penicillium oxalicum (fungi specie). The effects of three parameters on the microbial behavior were studied : the relative humidity (RH) of the air, the filter material, the airflow presence/absence. Whatever conditions, S. epidermidis did not grow up. However, P. oxalicum has demonstrated its ability to develop itself when RH was close to 100% and some P. oxalicumspores were released downstream of filter after growth, when ventilation was restarted. The second part of the thesis consisted in working with a semi-urban outdoor air. Two air handling unit (AHU) have operated during 5 months. The ventilation of one AHU was stopped each week-end and restarted each beginning of week. Temperature and RH of the air, filters pressure drop and total concentration of PM in air before filtration were monitored. Concentration of total cultivable microorganisms upstream and downstream of both filters was also measured each week, in particular at the restart of ventilation for one AHU. According to seasonal variations of microbial concentrations, results have revealed for instance that the filtration efficiency of cultivable bacteria was particularly weak, and sometimes negative, for the AHU operating continuously.
86

Outils numériques et technologiques pour l'analyse de la qualité de l'air intérieur / Technological and numerical tools for indoor air quality monitoring

César, William 05 March 2014 (has links)
L'objectif de cette thèse est le développement d'outils technologiques et logiciels permettant un monitoring de la qualité de l'air intérieur. Cela comprend la conception de capteurs miniaturisés permettant la détection simultanée d'un grand nombre de polluants, ainsi que le développement de modèles numériques inverses utilisant les données issues de ces capteurs et permettant la reconstruction de sources de polluants. Ces travaux ont mené à l'élaboration d'un prototype fonctionnel de micro-chromatographe en phase gazeuse, système d'analyse chimique miniaturisé permettant la détection de multiples polluants. La colonne de séparation fabriquée en technologie MEMS a permis la séparation de divers composés organiques volatils en quelques dizaines de secondes. Le micro-détecteur TCD, fondé sur une mesure 4-pointes couplée à un circuit d'asservissement en température original, a permis la détection des composés séparés dans la colonne. Afin d'améliorer et de tirer au mieux parti des micro-chromatographes, des méthodes d'injections stochastiques ont été développées. Il a été démontré que ces méthodes ont plusieurs intérêts. D'une part, elles permettent facilement un gain de rapport signal/bruit de l'ordre de la décade, ce qui permet la détection de polluants plus faiblement concentrés. Il a été observé d'autre part qu'il est possible de suivre en temps réel l'évolution moyenne de la concentration des polluants alors que cela n'est pas possible lorsque le chromatographe est utilisé de manière standard. Enfin, une méthode d'injection et de traitement du signal permettant l'analyse simultanée de plusieurs échantillons avec un unique capteur a été développée. Enfin, ces travaux ont été complétés par le développement de modèles inverses 2D permettant, à partir de données issues de micro-chromatographes placés dans l'espace, la reconstruction de sources de polluants et de champs de vitesses par méthode des gaz traceur. Ces modèles sont fondés sur une approche de contrôle optimal et utilisent une résolution des équations de Navier-Stokes et de diffusion-advection par la méthode éléments finis. L'utilisation de bases orthonormées obtenues par POD a permis de régulariser ces modèles inverses / The goal of this thesis is the development of technological and numerical tools for the monitoring of indoor air quality. That comprises the design of miniaturized sensors capable of detecting a large number of pollutants, and the development of inverse models allowing the reconstruction of pollutant sources from concentration measurements. In this work we present the realization of a micro-gas chromatograph, miniaturized chemical-analysis system fabricated with silicon-based MEMS technology. The separation column can separate multiple volatile organic compounds in less than a minute. The integrated thermal conductivity detector, based on a 4-points measurement technique coupled with an original temperature control circuit, can detect compounds separated in the column. In order to improve the performances of such micro-chromatographs, stochastic injection techniques have been developped. We have shown that these techniques easily allow to reduce the detection noise by an order of magnitude so that low-concentrated pollutants can be detected. We also observed that it is possible to follow in real time the mean evolution of the concentration with such techniques. We finally developped an original multiplexing technique that allows to monitor multiple sample streams simultaneoulsy with a single sensor. Finally, this work is completed by the development of 2D inverse models that allow, from data measured by micro-chromatographs placed in a room, to reconstruct pollutant sources, concentration fields or airflow patterns. Those models are based on an optimal control approach and use the resolution of Navier-Stokes and diffusion-advection equations with the finite element method. POD orthonormal basis are used for the regularization of the problem
87

Evaluation expérimentale des performances des systèmes de ventilation dans le bâtiment : efficacité de ventilation et confort thermique / Building ventilation performance assessement : ventilation efficiency and thermal comfort

Allab, Yacine 12 December 2017 (has links)
La performance d’un système doit être bien définie, atteignable et surtout mesurable. Ce n’est pas le cas aujourd’hui pour la ventilation. D’une part, les performances des systèmes de ventilation sont habituellement exprimées sur des considérations énergétiques ou tout simplement sur une estimation trop approximative des débits de ventilation. Les performances liées au confort thermique et à la qualité de l’air intérieur sont abordées séparément à travers des outils d’évaluation dédiés. D’autre part, les outils d’évaluation existants sont aujourd’hui limités dans leur mise en pratique pour des mesures in situ, notamment lorsqu’il s’agit de ventilation naturelle et mixte. L’objectif de cette thèse est alors d’examiner et d’expérimenter les techniques expérimentales existantes à échelle réelle afin de proposer des améliorations sur les méthodes d’évaluation et de commissionnement. La thèse aborde la performance de la ventilation en prenant en compte l’efficacité de ventilation comme performance intrinsèque et le confort thermique comme performance globale.La première partie est consacrée à l’évaluation in situ des performances intrinsèques de ventilation (taux de ventilation, âges moyens de l’air et efficacité de renouvellement d’air), en se basant sur des techniques de gaz traceurs. Après une analyse théorique des différents indicateurs de performance de ventilation et de leurs techniques de mesure correspondantes, une étude expérimentale a été menée dans une salle de cours sous différentes stratégies de ventilation (mécanique, naturelle et mixte). Les analyses ont démontré l’importance de la mise en application des techniques de décroissance de gaz traceurs sur l’incertitude des taux de renouvellement d’air avec notamment une forte influence des temps de mesure et des concentrations de gaz utilisées. Une méthodologie a été adaptée puis testée pour la mesure de l’efficacité de renouvellement d’air en ventilation mécanique, naturelle et mixte en s’affranchissant de mesures en bouches d’extraction (technique habituellement utilisée et préconisée par les normes).La deuxième partie est consacrée à l’évaluation expérimentale in situ du confort thermique sous différentes configurations de ventilation. Différentes méthodes, standards et techniques d’évaluation ont été testés et comparés avec la perception des occupants. Les résultats ont démontré la présence de plusieurs inadéquations lors de la mise en pratique des méthodes et normes existantes. Principalement, il s’agit de l’inadéquation des méthodes statiques (PMV PPD) pour l’évaluation du confort en présence de conditions thermiques fluctuantes, y compris en ventilation mécanique. Les analyses d’incertitudes liées aux erreurs de mesure ont démontré l’incohérence des normes actuelles dans la classification des catégories de confort. / The performance of a system must be well defined, attainable and above all measurable. This is not the case today for ventilation. On the one hand ventilation performance is usually declined on energy efficiency considerations or simply on a rough estimation of ventilation rates. The performance related to thermal comfort and IAQ are addressed separately through dedicated evaluation tools. On the other hand, the existing evaluation tools today are nowadays limited in their practical applications for in situ measurements, in particular in the case of natural and mixed ventilation. The aim of the present thesis is to examine the existing experimental technics, at full scale building in order to propose improvements on evaluation methods and commissioning protocols. The present thesis deals with ventilation performance taking into account ventilation efficiency as intrinsic performance and thermal comfort as overall performance.The first part is devoted to the in situ assessment of intrinsic ventilation performance (ventilation rates, mean age of air, and air exchange efficiency), based on decay tracer gas techniques. After a theorical analysis of the various performance indexes and their corresponding measurement techniques, an experimental study was carried out in a classroom under different ventilation strategies (mechanical, natural & mixed mode). The analysis proved the importance of the application of the tracer gas decay on ventilation rates accuracy with in particular a strong influence of measurement times and used tracer gas concentration. A methodology has been adapted and tested for the measurement of the air exchange efficiency in natural and mixed mode ventilation, by avoiding measurements in exhaust vents (a technique usually used and advocated by current standards).The second part is devoted to in situ assessment of thermal comfort under different ventilation strategies. Different methods, standards and evaluation techniques were tested and compared with occupants’ perception. The results demonstrated the presence of several inadequacies during the implementation of existing methods and standards. Mainly, it concerns the inadequacy of static methods (PMV PPD) for thermal comfort assessment in the presence of fluctuating thermal conditions, even with mechanical ventilation. Uncertainty analysis related to measurement errors has demonstrated the incoherence of current standards in the classification of comfort categories.
88

Avaliação da qualidade do ar de cabines de veículos automotores recém-manufaturados / Evaluation of new vehicles cabin indoor air quality

Valvassori Filho, Auzebio 23 September 2008 (has links)
Cabines de veículos automotores recém-manufaturados podem ser consideradas críticas quando se avalia a qualidade do ar interno, pois concentrações de compostos orgânicos voláteis encontram-se em níveis mais altos que os ambientes externos. Determinadas substâncias presentes no ar da cabine podem ser prejudiciais ao ser humano em função da sua toxicidade, pricipalmente nos grandes centros urbanos. A avaliação do ar da cabine automotiva se faz necessária. Nesse estudo, foi feita uma avaliação da qualidade do ar interno da cabine de 7 veículos populares recém-manufaturados contendo materiais de acabamento interno iguais. Um total de 46 compostos orgânicos voláteis foi identificado, sendo que 14 deles são compostos carbonílicos e 32 são hidrocarbonetos alifáticos e aromáticos, compostos halogenados e um nitrogenado. Os compostos carbonílicos foram identificados e quantificados por cromatografia a líquido e os outros VOCs apenas identificados por GC-MS. No ar interno da cabine dos veículos estudados, as concentrações médias encontradas para os compostos carbonílicos (&#181;g/m3) em ordem decrescente foram: formaldeído (165,3); acetona (67,5); acetaldeído (56,8); isovaleraldeído (40,8); propionaldeído (21,1); butiraldeído (17,9); crotonaldeído (14,9); hexaldeído (14,9) valeraldeído (9,8); 2.5- dimetilbenzaldeído (9,3); otolualdeído (8,4); p/m tolualdeído (6,8); acroleína (4,2) e benzaldeído (3,8). Com relação aos outros VOCS foram identificados o metilbutano, que apresentou a maior porcentagem de abundância relativa, 8,5%, seguido de outros hidrocarbonetos com abundância relativa entre 5 e 2% , como, 2,7,10-trimetildodecano, 2,2,6-trimetildecano, ciclopentano, 2,3,4-trimetildecano, n-pentano, 3,6-dimetilundecano, 4-metildodecano, 4,6- dimetildodecano, 3,6-dimetildecano e 1,2-dimetilbenzeno. Dois derivados de hidrocarbonetos halogenados também foram encontrados, sendo que o triclorofluormetano foi o majoritário com 5,7%, e um composto nitrogenado, a acetonitrila com 5,4%. Os compostos derivados do benzeno identificados foram: 1,2-dimetilbenzeno, etilbenzeno, metilbenzeno, 1-etil-3- metilbenzeno, 1-etil-3-metilbenzeno e 1,3,5-trimetilbenzeno que perfazem 6,6 % de abundância relativa. O mais abundante entre os aromáticos foi o 1,2-dimetilbenzeno (2,5%). Os resultados experimentais revelaram também a liberação de VOCs pelos materiais de acabamento interno dos veículos automotores recém-manufaturados. / New motor vehicles cabins may be critical when considering the internal air quality, because concentrations of volatile organic compounds are at levels higher than the outdoors. Certain substances present in the cabin air can be harmful to humans according to their toxicity, mainly in the big cities. Assessment of the cabin air becomes necessary. In this study, cabin air quality was assessed and 7 popular new vehicles containing same interior trim materials were evaluated. A total of 46 volatile organic compounds were identified, with 14 of them were carbonylic compounds and 32 are aliphatic and aromatic hydrocarbons, halogenated compounds and a nitrogenated compound. The carbonylic compounds were identified and quantified by the liquid chromatography and other VOCs only identified by GC-MS. Cabin air vehicles studied showed the following average concentrations found for carbonylic compounds ( &#181;g/m3) in a descending order: formaldehyde (165.3), acetone (67.5); acetaldehyde (56.8); Isovaleraldehyde ( 40.8); propionaldehyde (21.1); butyraldehyde (17.9); crotonaldeído (14.9); hexaldeído (14.9) Valeraldehyde (9.8); dimetilbenzaldeído-2.5 (9.3); the - tolualdeído (8.4), p / m - tolualdeído (6.8); acrolein (4.2) and benzaldehyde (3.8). Concerning the other VOCs the following compounds were identified: methylbutane, which had the highest percentage of relative abundance, 8.5%, followed by other hydrocarbons with relative abundance between 5 and 2%, 2,7,10-trimetildodecano, 2.2 ,6- Trimetildecano, ciclopentano, 2,3,4-trimetildecano, n-pentane, 3.6-dimetilundecano, 4- metildodecano, dimetildodecano-4.6, 3.6 and 1.2-dimetildecano-dimetilbenzeno. Two halogenated hydrocarbons were also found, and triclorofluormetano had the biggest relative abundance percentage 5.7%, and a nitrogen compound, the acetonitrile with 5.4%. The benzene compounds identified were: 1.2-dimetilbenzeno, ethylbenzene, methylbenzene, 1- ethyl-3-methyl, ethyl-1-and 3-methyl 1,3,5-trimethylbenzene which comprise 6.6% of relative abundance. 1.2-dimetilbenzeno was the most abundant aromatic compound with relative abundance 2.5%. Results also showed that VOCs were released by studied vehicles interior trim materials.
89

Qualidade do ar interno com ênfase na concentração de aerodispersóides nos edifícios. / The indoor air quality in the buildings with an emphasis on the concentration of particulates matters.

Moraes, Alexandre Perri de 28 June 2006 (has links)
No presente trabalho, é avaliada a qualidade do ar interno com ênfase na concentração de aerodispersóides presentes em edifícios comerciais e residenciais com sistema de ventilação natural ou condicionamento de ar. De fato, algumas doenças de origem ocupacional são causadas pela inalação de aerodispersóides nocivos à saúde. O método utilizado para avaliar a qualidade do ar interno nos edifícios comerciais e residenciais consistiu primeiramente em caracterizar os medidores de aerodispersóides e em seguida passou-se para a análise das concentrações e das características ambientais. A pesquisa mediu a concentração de aerodispersóides em edifícios com sistemas de ventilação diferentes (1a fase), e identificou as principais fontes de emissão de aerodispersóides em um apartamento residencial (2a fase). Observou-se que as concentrações obtidas na pesquisa estão acima dos valores recomendados na RE n° 9 (ANVISA, 2003) e por Morawska et al. (1999) que atribuem valores de 80 µg/m³ e 7.400 part./cm³, para concentrações médias em massa e em número, respectivamente. Com base nas observações acima, chegou à conclusão que as concentrações médias em massa e em número de aerodispersóides, durante as atividades domésticas (cozimento, reforma, limpeza, entre outras), foram várias vezes maiores do que as concentrações obtidas em ambientes com atividades profissionais ou com menor ocupação durante o dia. / This paper is the result of quality evaluation of indoor air quality with emphasis on the concentration of aerodispersoid in commercial and residential buildings with natural ventilation or air conditioning systems. In fact, some of the occupational diseases are caused by the inhalation of aerodispersoids hazardous to health. The method applied to evaluate the indoor air quality in commercial and residential buildings consisted firstly of characterizing the aerodispersoid measuring devices and subsequently analyzing the concentration levels and environmental characteristics. This research measured the concentration of aerodispersoids in buildings equipped with a variety of ventilation systems (phase1) and next it identified the main emission sources in a residential apartment (phase 2). It was observed that the concentration levels measured were above the specifications recommended by RE n° 9 (ANVISA, 2003) and by Morawska et al. (1999) which attribute values of 80 µg/m³ and 7.400 part./cm³, for average concentration in mass and number respectively. Based on the above information it was concluded that the average concentration levels of aerodispersoids in mass and number in home related activities (cooking, restoration, cleaning, etc) were many times higher than the concentration levels found in business environments or in environments with less occupation during the day.
90

Particulate matter inside residences of elderly in the Metropolitan Area of São Paulo / Material particulado em residências de idosos na Região Metropolitana de São Paulo.

Segalin, Bruna 24 November 2017 (has links)
The elderly population is sensitive to damages caused by air pollution on health. They spend relatively more time indoors, however there is limited information on the air quality they breathe inside their residences. The objectives of this work are to characterise mass of sizesegregated particulate matter (PM) in elderly residences in Metropolitan Area of Sao Paulo (MASP) in Brazil; assess the meteorological parameters influence; evaluate the indoor and outdoor relationship of PM; quantify the ions, trace elements and black carbon (rBC) in quasi-ultrafine particles (qUFP) and identify their sources, and estimate the respiratory deposition doses (RDD). To achieve these objectives, we measured during 24 hours the mass concentrations of PM in differents sizes (102.5, 2.51.0, 1.00.5, 0.50.25 and <0.25 µm (PM0.25, qUFP) in 59 elderly residences in MASP using a Personal Cascade Impactor Sampler. The PM10 is the sum of all size and PM2.5 is PM10 less PM102.5. The PM2.5 and PM0.25 contributed 78% and 38% of total PM10, respectively. About 77% and 40% of the residences had higher PM2.5 and PM10 than those in outdoor environments. About 13 and 43% of the measurements exceeded the World Health Organization (WHO) guidelines for PM10 and PM2.5, respectively. The PM0.25 exceeded the WHO guideline for PM2.5 in 8.3% of residences. Residences with higher PM concentration in all size bins are predominantly near the heavy traffic areas during the nonprecipitation days. About 68% of residences have the highest mass concentration in PM0.25. We analysed ions by chromatography, trace elements by x-ray fluorescence and rBC by reflectance. The major of ions concentrations in qUFP were found to be SO42- and NH4+, and the major trace elements were Si and Fe. Around 26% of the qUFP is rBC. Some residences have a high concentration of the toxic heavy metals Cu, Ni, Pb and Cr. We identified 6 dominant sources of the indoor qUFP by positive matrix factorization: vehicular emission (57%), secondary inorganic aerosol (21%), soil and construction (7%), wall painting (7%), cooking (5%) and industry (3%). The RDD for coarse and fine particles were found to be 20% and 24.6% higher for male than female elderly during seated position, respectively. The maximum RDD of qUFP and rBC are in the tracheobronchial part. It is important the control of PM sources in the elderly residences to limit adverse health effects of PM, especially fine particles. We suggest consider the rBC as one regulated air pollutant in terms of public control actions for air quality improvement in MASP. / A população idosa é sensível aos riscos da poluição do ar à saúde. Os idosos passam mais tempo dentro de suas casas, mas há pouca informação sobre a qualidade do ar dentro de suas residências. Os objetivos deste trabalho são caracterizar a massa do material particulado (PM) de diferentes tamanhos em residências de idosos na Região Metropolitana de São Paulo (RMSP) no Brasil; avaliar a influência dos parâmetros meteorológicos e a relação entre PM de ambiente interno e externo; quantificar os íons, elementos traços e black carbon (rBC) em partículas quasi-ultrafinas (qUFP) e identificar suas fontes, e estimar as doses de deposição de PM no trato respiratório (RDD). Para alcançar esses objetivos, medimos durante 24 horas as concentrações em massa de PM nos tamanhos 10-2,5; 2,5-1,0; 1,0-0,5; 0,5-0,25 e <0,25 m (PM0.25, qUFP) em 59 residências de idosos na RMSP usando o Personal Cascade Impactor Sampler. O PM10 é a soma da massa em todos os tamanhos e PM2.5 é o PM10 menos o PM10-2.5. O PM2.5 e PM0.25 contribuíram com 78% e 38% do total de PM10, respectivamente. Cerca de 77% e 40% das residências apresentaram maior concentração de PM2.5 e PM10 do que aqueles em ambientes externos. Cerca de 13 e 43% das medidas excederam as diretrizes da Organização Mundial de Saúde (OMS) para PM10 e PM2.5, respectivamente. O PM0.25 excedeu o limiar da OMS para PM2.5 em 8.3% das residências. As residências com maior concentração de PM em todos os tamanhos estão próximas das áreas de intenso tráfego veicular e não houve precipitação durante a medição. Cerca de 68% das residências têm a maior concentração de massa em PM0.25. Analisamos os íons por cromatografia, elementos traços por fluorescência de raios-x e rBC por reflectância. A maior concentração de íons em qUFP foi SO42- e NH4+, e os principais elementos traços foram Si e Fe. Cerca de 26% do qUFP é rBC. Algumas residências têm uma alta concentração dos metais pesados tóxicos Cu, Ni, Pb e Cr. Identificou-se 6 fontes de qUFP por fatoração de matriz positiva: emissão de veículos (57%), aerossol inorgânico secundário (21%), solo e construção (7%), pintura de parede (7%), cozimento (5%) e indústria (3%). O RDD para PM10-2.5 e PM2.5 foi 20% e 24,6% maior para homens do que mulheres enquanto sentados, respectivamente. O RDD máximo de qUFP e rBC foi na parte traqueobrônquica. É importante o controle de fontes de PM nas residências de idosos para limitar os efeitos adversos à saúde, especialmente partículas finas. Sugerimos considerar o rBC como um poluente atmosférico regulado em termos de ações de controle público para a melhoria da qualidade do ar na RMSP.

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