Nos últimos anos tem havido um aumento no estudo da qualidade do ar interno relacionado aos sistemas de ventilação mecânica e condicionamento do ar. Isso é especialmente fundamental em hospitais, onde a transmissão da contaminação pelo ar é considerada uma das principais causas de aquisição de doenças por pacientes, profissionais de saúde e visitantes. Além disso, essas instituições por abrigarem diversos setores, cada um com uma especificidade e função, exigem diferentes condições de conforto ambiental, sob os aspectos higrotérmico e de qualidade do ar, além do acústico e luminoso. Com o objetivo de avaliar a qualidade o ar, sob os parâmetros de conforto térmico e da concentração de dióxido de carbono em ambientes hospitalares climatizados artificialmente, realizou-se uma investigação de campo em salas de espera e salas de cirurgias de uma amostra de seis edifícios hospitalares na cidade de São Paulo e região metropolitana. Para coleta dos dados foram utilizados instrumentos de monitoramento, portáteis e de elevada precisão, adequados para a realização da pesquisa. Os resultados obtidos a partir da análise desses dados apontaram relevantes problemas relacionados ao conforto e a qualidade do ar. Dentre esses problemas, destacam-se a ausência de controle do diferencial de pressão entre as salas de cirurgias e os corredores; a divergência entre as temperaturas operativas ideais para promoção do conforto térmico para grupos de pessoas com diferentes vestimentas e nível de atividade, ocupando um mesmo ambiente, no caso, as salas de cirurgias; a insuficiência de renovação de ar, especialmente nas salas de espera equipadas com o sistema de climatização do tipo split-system; além da ausência de padronização entre os critérios dos referenciais técnicos mais adotados. Sob esses aspectos, percebeu-se a necessidade de melhoria do conhecimento da interação entre os ocupantes e o ambiente, especialmente naqueles onde o controle se faz necessário para a promoção da saúde. / In recent years has been increased interest in thermal comfort and air quality of indoor environments related to mechanical ventilation systems and air conditioning. This is especially crucial in hospitals where contaminated air transmission is considered a major cause of acquiring disease for patients, health care professionals and visitors. Moreover, these institutions having different sectors, each one with a speciality and function, require different conditions of environmental comfort, in terms of hygrothermal, air quality, acoustic and luminous aspects. In order to evaluate the air quality under the parameters of thermal comfort and carbon dioxide concentration in air conditioning hospital environments, it was carried out a field investigation in waiting rooms and operating rooms in six hospitals in São Paulo and metropolitan region. For data collection were used portable monitoring devices, suitable for research. The results from data analysis indicated significant problems related to thermal comfort and indoor air quality. Among these problems, it can be highlighted the lack of the differential pressure control between the operating rooms and corridors; the divergence among the optimal operative temperatures to provide thermal comfort for different groups of people with different clothing and activity level, occupying the same environment, in this case, the operating rooms; the disregard with the air changes required, especially in waiting rooms equipped with the splitsystem; besides the lack of standardization among the technical references criteria often used. Under these aspects, it is necessary to improve the knowledge of the interaction between the occupants and the environment, especially where the environmental control is decisive to promote the health.

Este trabalho apresenta uma caracterização ambiental do Mercado Municipal da cidade de São Carlos-SP, localizado na região central da cidade, onde ocorre grande movimentação de pessoas e veículos, em horário comercial. Foram analisados os níveis de material particulado em suspensão no ar, nas suas frações MP10 e MP2,5, níveis de ruído, temperatura e umidade relativa do ar relativa, nos ambientes internos e externos do Mercado. Os valores das concentrações de material particulado, tanto para MP10, como MP2,5, apresentaram-se, em geral, maiores no ambiente interno do que no externo. Os valores encontrados para MP2,5 chegaram a 66,60 g/m³, no ambiente interno, e 60,56 g/m³, no externo. Para a fração MP10, a concentração interna alcançou o valor de 117,74 g/m³ e a externa atingiu os 134,51 g/m³. Duas metodologias diferentes foram utilizadas para a determinação da concentração de material particulado em suspensão, a gravimetria pelo Personal Enviromental Monitor (PEM), e a fotometria por espalhamento de luz pelo aparelho ADR-1500 e pDR-1500. A técnica da gravimetria apresentou, em geral, os valores mais elevados. Uma análise do material particulado foi realizada, por meio da técnica de Fluorescência de Raio-X, para identificação dos elementos químicos presentes. Foram encontrados: Ba, Ca, K, Zn, S, Fe, e Rb. Já em relação à temperatura e umidade relativa do ar, os níveis oscilaram bastante durante o dia, com médias da temperatura interna entre 14°C e 34°C, e a umidade com valores entre 19% e 58%. Foi calculado o Índice de Calor (Hi - Heat Index), revelando desconforto térmico na maior parte dos dias, com as temperaturas internas normalmente acima das externas. Os níveis de ruído encontrados no ambiente interno e externo chegaram a 71,42 e 85,43 dB(A), respectivamente. Foi aplicado um questionário sobre qualidade ambiental aos funcionários do Mercado: 67% dos respondentes acham o local muito quente e 33 % consideram o local muito ruidoso. / This study presents an environmental characterization of the Municipal Market in the city of São Carlos, SP, located at the downtown area, where there is a great movement of people and vehicles, mainly during business hours. The levels of suspended particulate matter in the air were analyzed, in its fractions PM10 and PM2,5, noise levels, temperature and relative humidity in indoor and outdoor environments of the Market. The concentrations of the particulate material for both MP10 and PM2,5, are presented in general higher in the internal environment than the outer and exceeded the limits of the World Health Organization-WHO. The values for PM2,5 reached to 66,60 g/m³, the internal environment, and 60,56 g/m³, externally. For PM10 fraction, the internal concentration reached a value of 117,74 g/m³ and external reached 134,51 g/m³. Two different methods were used to determine the concentration of suspended particulate matter, gravimetry by The Environmental Monitor-PEM and light scattering photometric by the device ADR-1500 and pDR-1500. The gravimetric technique showed in general the highest values. An analysis of the particulate matter was performed by the technique of X-ray fluorescence for the identification of chemical elements. Were found: Ba, Ca, K, Zn, Fe and Rb. In relation to temperature and relative humidity, levels oscillated during the day, with average of the internal temperature between 14°C and 34°C, and humidity with values between 19% and 58%. Were calculated the Heat Index (Hi), revealing thermal discomfort in most of the days, with internal temperatures usually above the external. The noise levels in the internal and external environment reached 71,42 and 85,43 dB(A), respectively. A questionnaire about the environmental quality was applied on the officials Market: 67% of respondents thought the place was very hot and 33% considered the place very noisy.

In June 2008, the Cedar River crested flooding more than 5,000 Cedar Rapids homes. Residents whose homes were flooded were invited to participate in this study. We characterized exposures and symptoms experienced by individuals inhabiting 73 flood-damaged homes. Exposures and questionnaire-based health assessments were compared at two levels of remediation, in-progress and completed. Homes with remediation in-progress (n=24), as compared to the completed homes (n=49), had significantly higher airborne concentrations of mold, bacteria, iPM, endotoxin and glucan. Residents of in-progress homes had a significantly higher prevalence of doctor diagnosed allergies (adjusted OR=3.08; 95%CI: 1.05-9.02) and all residents had elevated prevalence of self-reported wheeze (adjusted OR=3.77; 95%CI: 2.06-6.92) and prescription medication use for breathing problems (adjusted OR=1.38; 95%CI: 1.01-1.88) after the flood as compared to before. Proper post-flood remediation led to improved air quality and lower exposures among residents living in flooded homes. Recognition of endotoxin as a proinflammatory ligand for pattern recognition receptors has increased the demand for endotoxin assessment in studies of environmental lung disease. Measurements using the Limulus amebocyte lysate (LAL) assay of air and reservoir dust samples are routinely incorporated into epidemiologic studies. However, it is unknown if endotoxin reactivity in the LAL assay varies by its physical presentation as aggregates, as membrane components of whole bacteria or as shed membrane blebs or if this parallels differences in the inflammatory potency of endotoxin in vivo. Endotoxins as14C-labeled-lipooligosaccharide (14C-LOS) and 14C- labeled-lipopolysaccharide (14C-LPS) were produced from Neisseria meningitidis and Escherichia coli. The reactivity of the endotoxin presentations was assessed in the LAL assay and in vivo using a murine model. The LAL assay significantly underestimated the quantity of endotoxin in the whole bacteria form whereas there was no significant difference in detecting endotoxin in aggregate and bleb forms. The failure of the LAL assay to equally quantify endotoxin was not mirrored in vivo where all three presentations of endotoxin were equally inflammatory. The inability of the LAL assay to detect the full quantity of endotoxin presented in the whole bacteria form has troubling implications for exposure assessment studies. Various extraction methods were applied to samples of known endotoxin quantity to improve the detection ability of the LAL assay. Extraction using EDTA and Tris/EDTA significantly improved the detection of endotoxin compared to the reference method of extracting in pyrogen-free water. These extraction methods also significantly increased the quantity of endotoxin measured in house and barn dust samples. A higher quantity of endotoxin measured in the LAL assay corresponded to a higher neutrophilic response in vivo. A standardized methodology for endotoxin detection that mimics the in vivo response is necessary for accurate and consistent endotoxin analysis.

Ozone in indoor environments can pose a health risk to human occupants; around half of exposure to this pollutant occurs inside buildings. One approach to reducing indoor O3 levels is to mitigate O3 as it enters a building via outdoor air ventilation supply. Often, mechanical systems that introduce outdoor air into buildings are placed on building rooftops. At the urban scale, greenery has been shown to reduce levels of some harmful pollutants, including ozone and cities like Portland, OR, are mandating green roofs be built on large commercial buildings to increase urban green surfaces. We investigate if rooftop vegetation may act as a sink for O3 as transport occurs across a green roof. It is known that O3 can react with vegetated surfaces and the ground but there is scant empirical research on said pollutant dynamics on vegetated green roofs, and little data concerning pollutant interactions occurring on other rooftop designs. Essentially unstudied is the potential of rooftop designs to affect local concentrations of pollutants where building outdoor air supply may be co-located. In this study, we investigate O3 dry deposition using resistance uptake theory in an area that includes a green roof on a local big box retail store through a field study conducted during a two-week period in the Summer of 2017. Deposition velocities and subsequently surface resistances were measured. The 10th, 50th, and 90th percentiles for resistances were 54.8 s/m, 195.3 s/m, and 3692.9 s/m respectively. A 2-D advection-diffusion model of rooftop deposition is employed to describe transport across the green roof and sensitivity analysis was performed to compare the impact of different parameters. The sensitivity analysis demonstrated that the fetch length and the vegetation height had the biggest impact, followed by the meteorological parameters; the friction velocity and heat flux. The surface resistance had the least impact on deposition. An ideal case was used to demonstrate that even when conditions are maximized for deposition, the impact on the concentration gradient is minimal at best.

In this thesis the sink-effect in indoor materials wasstudied using mathematical modelling and experimental studies.The sink-effect is a concept which is commonly used tocharacterise the ability of different indoor materials to sorbcontaminants present in the indoor air. The sorption process ismore or less reversible, i.e. molecules sorbed in materials athigh contaminant concentrations may again be desorbed at lowerconcentrations. Knowledge of the sorption capacity of materialsand the rate at which sorption and desorption takes place is offundamental importance for mathematical simulation of indoorair quality. The aim of this work is to contribute withknowledge about how the sink-effect can be described inmathematical terms and how the interaction parametersdescribing the sorption capacity and sorption/desorptionkinetics can be determined. The work has been of amethodological nature. The procedure has been to set upphysically sound mathematical models of varying complexity andto develop small-scale chamber experiments. Two differentdynamic chamber methods have been used. One is based on amodified standard FLEC-chamber while the other uses a chamberwith two compartments, one on each side of the material. The"twin-compartment" method was designed due to the observationthat the contaminant readily permeated straight through theselected materials, which resulted in uncontrolled radiallosses in the FLEC-chamber. In order to be useful forcomparison between experiments and calculations and parameterfitting, the boundary conditions in the chambers must beprecisely known and controlled. This matter has shown to be themost crucial and difficult problem in the research. A varietyof mathematical models for the sink-effect have been proposed.In some models advanced fluid simulations were used in order totest the influence ofill-defined flow boundary conditions. Theaim of the modelling is to find a formulation with a minimum ofinteraction parameters, which is generally useful, i.e. both insmall-scale laboratory environments and in full-scale like anoffice room. Estimated model parameters are shown to be able toyield a reasonably good fit to experimental data for thesorption process but a less satisfactory fit for the desorptionprocess. <b>Keywords:</b>sink-effect, sorption, adsorption, diffusion,indoor air quality, volatile organic compounds, VOC,contaminants, building materials

As building codes and green building programs require tighter home construction, the need for outdoor air ventilation to improve indoor air quality increases. Major improvements in building envelopes and duct systems have led to decreases in heating and cooling loads causing fewer HVAC system run-time hours, and increasing the probability for air stagnation within homes with poor outdoor air ventilation. ASHRAE Standard 62.2 quantifies the amount of whole-house ventilation required based on the number of occupants and the square footage of conditioned space, but leaves the design of the ventilation system up to the mechanical engineer or HVAC contractor. In 2010, ASHRAE began requiring flow testing for confirmation of outdoor air ventilation rates, yet few municipalities and green building programs have adopted the new standard. Builders in mixed-humid climates are forced to balance the need for outdoor air ventilation with the upfront costs for mechanical ventilation systems, and the potential for increased humidity loads and energy costs associated with mechanical ventilation strategies. One common solution employed in the southeastern United States involves a central fan integrated supply (CFIS) ventilation system controlled with an air-cycler for minimum run-time to meet ASHRAE Standard 62.2. While this system has been tested and proven to meet design ventilation rates, those tests were often conducted on homes constructed by well trained builders receiving strong oversight from building scientists and the design ventilation rates were not always ASHRAE compliant. The following report analyzes whether the CFIS ventilation system with air-cycler controller provides ventilation meeting ASHRAE Standard 62.2 when employed by builders with minimal training and support.

<p>In this thesis the sink-effect in indoor materials wasstudied using mathematical modelling and experimental studies.The sink-effect is a concept which is commonly used tocharacterise the ability of different indoor materials to sorbcontaminants present in the indoor air. The sorption process ismore or less reversible, i.e. molecules sorbed in materials athigh contaminant concentrations may again be desorbed at lowerconcentrations. Knowledge of the sorption capacity of materialsand the rate at which sorption and desorption takes place is offundamental importance for mathematical simulation of indoorair quality. The aim of this work is to contribute withknowledge about how the sink-effect can be described inmathematical terms and how the interaction parametersdescribing the sorption capacity and sorption/desorptionkinetics can be determined. The work has been of amethodological nature. The procedure has been to set upphysically sound mathematical models of varying complexity andto develop small-scale chamber experiments. Two differentdynamic chamber methods have been used. One is based on amodified standard FLEC-chamber while the other uses a chamberwith two compartments, one on each side of the material. The"twin-compartment" method was designed due to the observationthat the contaminant readily permeated straight through theselected materials, which resulted in uncontrolled radiallosses in the FLEC-chamber. In order to be useful forcomparison between experiments and calculations and parameterfitting, the boundary conditions in the chambers must beprecisely known and controlled. This matter has shown to be themost crucial and difficult problem in the research. A varietyof mathematical models for the sink-effect have been proposed.In some models advanced fluid simulations were used in order totest the influence ofill-defined flow boundary conditions. Theaim of the modelling is to find a formulation with a minimum ofinteraction parameters, which is generally useful, i.e. both insmall-scale laboratory environments and in full-scale like anoffice room. Estimated model parameters are shown to be able toyield a reasonably good fit to experimental data for thesorption process but a less satisfactory fit for the desorptionprocess.</p><p><b>Keywords:</b>sink-effect, sorption, adsorption, diffusion,indoor air quality, volatile organic compounds, VOC,contaminants, building materials</p>

Residential and light-commercial buildings comprise a significant portion of buildings in the United States. They account for a large fraction of the total amount of energy used in the U.S., and they also represent environments where people spend the majority of their time. Thus, the design, construction, and operation of these buildings and their systems greatly affect energy consumption and exposures to airborne pollutants of both indoor and outdoor origin. However, there remains a need to improve knowledge of some key source and removal mechanisms of indoor and outdoor pollutants in residential and light-commercial buildings, as well as their connections to energy use and peak electricity demand. Several standardized field test methods exist for characterizing energy use and indoor air quality in actual buildings, although few explicitly address residential and light-commercial buildings and they are generally limited in scope. Therefore, the work in this dissertation focuses on improving methods to characterize three particular building components for their impacts on exposures to indoor pollutants and their implications for energy consumption: (1) central forced-air heating and cooling (HAC) systems, (2) HAC filters, and (3) building envelopes. Specifically, the research in this dissertation is grouped to fulfill two primary objectives of developing and applying novel methods to: (1) characterize and evaluate central air-conditioning systems and their filters as pollutant removal devices in residential and light-commercial buildings, and to explore their implications for energy consumption, and (2) characterize and evaluate the ability of two particular outdoor pollutants of concern (ozone and particulate matter) to infiltrate indoors through leaks in building envelopes. The research in this dissertation is divided into four primary investigations that fulfill these two objectives. The first investigation (Investigation 1a) addresses Objective 1 by first providing a detailed characterization of a variety of operational characteristics measured in a sample of 17 existing central HAC systems in occupied residential and light-commercial buildings in Austin, Texas, and exploring their implications for exposure to indoor pollutants, energy use, and peak electricity demand. Among the findings in this study, central air-conditioning systems in occupied residential and light-commercial buildings did not operate most of the time, even in the hot and humid climate of Austin, Texas (i.e., ~25% of the time on average in the summer). However, average recirculation rates still make central air-conditioning systems competitive as particle removal mechanisms, given sufficient filtration efficiency. Additionally, this investigation used a larger, much broader, dataset of energy audits performed on nearly 5000 single-family homes in Austin to explore common inefficiencies in the building stock. Residential and light-commercial air-conditioning systems are often inefficient; in fact, residential central air-conditioning systems in particular likely account for nearly 20% of peak electric demand in the City of Austin. As much as 8% of peak demand could be saved by upgrading all single-family homes in Austin to higher-efficiency equipment. The second investigation (Investigation 1b) also addresses Objective 1 by developing and applying a novel test method for measuring the in-situ particle removal efficiency of HAC systems and filters in residential and light-commercial buildings. Results from the novel test method as performed with three test filters and 0.3–10 μm particles in an unoccupied test house agreed reasonably well with results from other field and laboratory test methods. Low-efficiency filters did not increase particle removal much more than simply running the HAC system without a filter, and higher-efficiency filters provided greater than ~50% removal efficiency for most particles greater than 1–2 μm in diameter. The benefit of this test method is that it can be used to measure how filters perform in actual environments, how filter removal efficiency changes with actual dust loading, and how much common HAC design and installation issues, such as low airflow rates, duct leakage, fouled coils, and filter bypass airflow, impact particle removal in real environments. The third investigation (Investigation 2a) addresses Objective 2 by developing and applying a novel test methodology for measuring the penetration of outdoor ozone, a reactive gas, through leaks in exterior building envelopes using a sample of 8 single-family residences in Austin, Texas. These measurements represent the first ever measurements of ozone penetration factors through building envelopes of which I am aware, and penetration factors were lower than the usual assumption of unity (i.e., P = 1) in seven of the eight test homes (ranging from 0.62±0.09 to 1.02±0.15), meaning that some building envelopes provide occupants with more protection from indoor exposures to ozone and ozone reaction byproducts than others. Additionally, ozone penetration factors were correlated with some building characteristics, including the amount of painted wood siding on the exterior envelope and the year of construction, suggesting that simple building details may be used to predict ozone infiltration into homes. Finally, the fourth investigation (Investigation 2b) also addresses Objective 2 by refining and applying a test methodology for measuring the penetration of ambient particulate matter through leaks in building envelopes, and using a sample of 19 single-family residences in Austin, Texas to explore correlations between experimentally-determined particle penetration factors and standardized fan pressurization air leakage tests. Penetration factors of particles 20–1000 nm in diameter ranged from 0.17±0.03 to 0.72±0.08 across 19 homes that relied solely on infiltration for ventilation air. Particle penetration factors were also significantly correlated with results from standardized fan pressurization (i.e., blower door) air leakage tests and the year of construction, suggesting that occupants of older and leakier homes are exposed to more particulate matter of outdoor origin than those in newer tighter homes. Additionally, blower door tests may actually offer some predictive ability of particle penetration factors in single-family homes, which could allow for vast improvements in making easier population exposure estimates. Overall, the work in this dissertation provides new methods and data for assessing the impacts of central air-conditioning systems, filters, and building envelopes on human exposure to indoor pollutants and energy use in residential and light-commercial buildings. Results from these four primary investigations will allow building scientists, modelers, system designers, policymakers, and health scientists to make better informed decisions and assumptions about source and removal mechanisms of indoor pollutants and their impacts on building energy consumption and peak electricity demand. / text

On November 7, 1973, President Nixon asked Americans to lower their home thermostats to a national average temperature of 68 degrees. On February 2, 1974, over half of the gas stations in the New York City area closed after selling out of fuel. These and other restrictions resulted from the Arab oil embargo of 1973-1974, a pivotal event in American history that made residential energy conservation an immediate national imperative. This dissertation situates American housing within the ecologically-oriented 1970s, when energy independence and environmental protection became political and popular priorities. I study two California communities that shared geographical and temporal proximity but responded to the energy crisis with divergent approaches to the ideal of energy-conserving, healthy housing. Part I explores early indoor environmental research at the Lawrence Berkeley Laboratory. In collaboration with utility companies, homebuilders, and homeowners, Berkeley’s researchers studied how residential energy conservation affected indoor air quality (IAQ) in conventional and alternative homes. Their goal was finding the “optimal balance” between equally vital goals: energy conservation, healthy indoor air, and cost-effectiveness. By the early 1980s, IAQ was the leading criterion in national conversations about healthy housing. Part II explores owner-built housing in 1970s California. Owner-builders embraced environmentalism and voluntary simplicity. Like Berkeley’s scientists, they pursued residential energy conservation, but did this either by living in minimalist cabins without heat or electricity,or by using alternative technologies (solar power, earth-building). Their top priority for housing was autonomy, not IAQ. They campaigned for the right to build their own low-cost housing unconstrained by building codes. They prioritized personal and planetary health in designing and building their homes, arguing that a healthy house was an instrument of social and environmental change. In juxtaposing these two approaches -- one academic and quantitative; the other holistic and iconoclastic -- I show that healthy housing has been a flexible ideal shaped by competing priorities: energy, health, affordability, and environmentalism. Housing, the fundamental link between people and the outdoor environment, is an ideal focus for environmental historians and adds another dimension to knowledge of American history since the energy crisis. / History of Science

In the first essay, I assess the effect of indoor air quality (IAQ) in school buildings on student test performance and attendance rates. Results indicate that performance on standardized tests significantly improves while attendance rates are unresponsive to improvements in IAQ. The improvement in math scores ranges from 0.102 - 0.189 standard deviations per $500,000 spent on IAQ-related renovations and is 35% - 50% greater than the improvement in reading scores. For the same budget, results suggest that the improvement in math scores following IAQ-related renovations is several times larger than the improvement associated with class size reductions. In the second essay, I examine the responsiveness of the daily labor supply of fishermen to transitory variations in the daily wage using data from the Florida spiny lobster fishery. The applicability of this research is both narrow and general. Understanding this relationship is key to determining the effectiveness of landing fees as a means to regulate fisheries. Tracing out the labor supply curve is also fundamental to labor economics and policy. I find that the wage elasticity of labor supply (participation) is positive and statistically different from zero, with a point estimate of 0.967. This suggests an upward slopping labor supply curve and refutes the notion of reference dependent preferences. In the third essay, I examine the bias associated with ignoring the multi-species aspect of labor supply decisions in spatially explicit bioeconomic fishery models. Using a complete 15-year panel of all fishing trips made by fishermen possessing a Florida spiny lobster license, including non-lobster trips, I show that the simplifying assumption of a dichotomous choice structure at the first node (i.e. participate in the target fishery or not) is not innocuous and that predicted participation rates can change substantially with the addition of another species as an outside alternative in the first decision node. / text