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RESUMO A areia descartada de fundição (ADF), um dos resíduos provenientes do processo de fabricação de peças e componentes em fundições, é um material rico em sílica, derivado de uma composição com areia natural, bastante fino em comparação com a matéria-prima natural corrente e classificado, pela norma brasileira NBR 10004, como resíduo classe II A, resíduo não perigoso e não inerte. Por ter características físicas interessantes para ser utilizado como um substituinte do agregado miúdo natural na produção de materiais à base de cimento Portland, uma análise da ADF foi realizada buscando sua utilização em concretos de cimento Portland. Após análise morfo-físico química da ADF, testes de incorporação em concretos de cimento Portland foram feitos e avaliados os desempenhos em várias proporções de substituição. Como avaliação final, ensaios mecânicos e de lixiviação foram realizados nos concretos de ADF e os resultados indicaram que há perda de desempenho mecânico com o aumento do teor de ADF, mas essa perda pode ser considerada pequena quando comparada com o valor ambiental da utilização da ADF como substituinte ao agregado natural na produção de concretos.

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The objectives of this study were to evaluate the thermal comfort and the similitude between prototypes and reduced models, using non-conventional coverage with green roof and expanded clay aggregate, supported on wood frame structure. For this, were determined the Black Globe Temperature and Humidity Index (BGHI), the Human Discomfort Index (HDI), Effective Temperature (ET), Air Temperature (Tair) and Radiant Thermal Load (RTL), from March 2013 to December 2014. The results showed that there were no statistical differences to 5% significance in predicting heat indices between the prototypes and models. Observing all indexes simultaneously, it was observed that January was the month what led to the worst heat conditions, while June and July showed the worst cold conditions. It can be concluded that the use of reduced models is possible (1:2) compared to the prototype (1:1), with green roofs and expanded clay as covering element, for the prediction of thermal indexes, minimizing construction costs and use of spaces.

Considering the time spent in enclosed environments, it is essential to study the relationship between pollutants and building ventilation systems to find whether the types and levels of pollutants and greenhouse gasses, which are expected to be exhaled through ventilation systems into the atmosphere, have been adequately evaluated. We propose the hypothesis that the exhaled air from residential buildings contains pollutants that may become another source of contamination affecting urban air quality and potentially contributing to climate drivers. Thus, the main goal of this article is to present a cross-review of the identification of pollutants expected to be exhaled through ventilation systems in residential buildings. This approach has created the concept of “exhalation of buildings” a new concept enclosed within the research project in which this article is included. We analyze the studies related to the most significant pollutants found in buildings and the studies about the relation of buildings' ventilation systems with such pollutants. Our results show that, on the one hand, the increase in the use of mechanical ventilation systems in residential buildings has been demonstrated to enhance the ventilation rate and generally improve the indoor air quality conditions. But no knowledge could be extracted about the corresponding environmental cost of this improvement, as no systematic data were found about the total mass of contaminants exhaled by those ventilation systems. At the same time, no projects were found that showed a quantitative study on exhalation from buildings, contrary to the existence of studies on pollutants in indoor air. Graphical Abstract

It is known that indoor air is affected by outdoor air, thanks to the various studies that have been conducted in this area, the causes can be varied, from infiltration of buildings, natural or mechanical ventilation. Although it is known that transportation is one of the major contributors to this problem, studies have concluded that there is a proportion of pollutants coming from 'non-specific sources of human origin', all this emphasizes the importance of identifying and quantifying the sources of air pollution.The intention of this research project, is to characterize and quantify the pollutants that are emitted from residential buildings through their ventilation systems, and how such exhalation affects urban air quality both outdoors and, through recapture, indoors.The design of a viable methodology for monitoring two residential buildings in Pamplona (Spain) has been proposed, involving aspects such as the extension of the city where the buildings selected for the project are located, their typology, the areas destined for the ventilation systems, the equipment chosen for the quantification of pollutants and the procedure to be followed. All this procedure represents the core of the monitoring process.Thanks to this methodology, the researchers intend to present results of the quantification of pollutants such as Carbon Dioxide (CO2), Carbon Monoxide (CO), Methane (CH4), Particulate Matter (PM), Volatile Organic Compounds (VOC), resulting from the exhalation of residential buildings. These results are the foundation for demonstrating how residential buildings can become another source of pollution for urban environments.

The issue of air pollutants from livestock buildings is prevalent in the literature. Because they and their emissions impact both animal production and livestock building users as well as the outdoor environment. This paper aims to compile and review data available in the scientific literature on the types of pollutants for a better understanding of their generation form, their distribution according to the kind of animal, and the main factors affecting their generation and concentration, i.e., the rearing system, the indoor microclimate, and the manure management. The elevated generation of pollutants in animal buildings is tied to the dense occupancy in this industrial activity. The indoor air quality is defined according to the type of livestock in animal housing, considering its welfare needs, and the types and concentrations of pollutants generated as a function of the family of animal and the management used in production. The main gases generated are CH4, CO2, H2S, NH3, N2O, in addition to particulate matter and airborne microorganisms such as fungi and bacteria that very negatively affect the health of animals and users of the animal buildings. Furthermore, knowledge about the main contaminants generated, the form of generation, their origin, their concentrations, and their distribution throughout the shed is essential to achieve a permanent and adequate indoor air quality and, with that, a high-quality product that will lead to high production yield without neglecting animal welfare.