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RESUMO: O município de Palmas-TO, localizado na região norte do Brasil, apresenta uma realidade climática com temperaturas altas durante todo o ano. Assim, é fundamental a busca por soluções tecnológicas que possam garantir o conforto higrotérmico nas residências, associado a reduções dos custos com energia necessária para o resfriamento da habitação. Nesta ótica, a constante inovação que o mercado mundial apresenta em produtos e técnicas voltadas para o resfriamento passivo de edificações justifica a realização de um estudo que avalie as condições higrotérmicas diante da implementação desses. O presente estudo apresenta os resultados de uma campanha experimental, com a duração de cerca de 5 meses, durante a qual foi avaliado o efeito da aplicação de diferentes técnicas de resfriamento passivo como: brise soleil, manta reflectante, ventilação natural cruzada e pintura com tinta reflectante. Para tal foram montadas duas células teste idênticas em Palmas-TO, tendo sido, em uma delas, implementadas as diferentes medidas de resfriamento passivo e a outra permanecido inalterada, para ser possível a comparação dos resultados. Verificou-se que a pintura com tinta reflectante apresentou maior redução de temperatura na média diária, obtendo seu melhor desempenho no período diurno e a ventilação natural cruzada foi a mais eficaz no período noturno. O brise soleil obteve uma redução de temperatura insignificante enquanto a manta reflectante mostrou-se nada eficaz nas condições de ensaio. ABSTRACT: The city of Palmas-TO, located in the northern region of Brazil, has a climatic reality with high temperatures throughout the year. Thus, it is essential to search for technological solutions that can guarantee better hygrothermal comfort in dwellings, associated with reductions in the cost of energy needed to cool it down. In this perspective, the constant innovation that the world market presents in products and techniques aimed at the passive cooling of buildings justifies to carry out a study to assess the hygrothermal conditions in dwelling after implementing those products / techniques. This study presents the results of an experimental campaign, lasting about 5 months, during which the effect of different passive cooling techniques was evaluated, such as: brise soleil, low-emissivity insolation, natural cross ventilation, and painting with reflective paint. For this purpose, two identical test cells in Palmas-TO were used. On one cell the different passive cooling measures were implemented and the other remained unchanged, in order to be able to compare the results. The painting with reflective paint showed the highest reduction in temperature in the daily average, obtaining its best performance during daytime. However, natural cross ventilation was the most effective technique during nighttime. The brise soleil achieved an insignificant temperature reduction while the low-emissivity insolation proved to be ineffective in these test conditions.

Building air infiltration performs two fundamental functions: it ensures the entry of fresh and clean air, improving the air quality inside buildings, and it promotes the withdrawal away of indoor pollutants. Understanding and quantifying the air renewal of a building is the first step towards a correct control and definition of its most adequate use strategy. In this context, computer simulation can play a fundamental role, allowing to estimate the variations of internal temperature, related to each strategy, helping the owner and/or designers in the decision-making process. The most common technique for measuring ventilation rates relies on the use of a tracer gas. In this work, air change rates were measured in a social house using the tracer gas method and the decay technique. For this purpose, five tests were carried out, allowing to evaluate the variability of the results. The results were then used as input in a simulation model using EnergyPlus 8.6 and DesignBuilder 5.5.2. The mean value of the air change rate obtained in the tests was 1.16 h-1, demonstrated that the increase in in the rate of infiltration ventilation in the residence, especially at night, contributes to the mitigation of discomfort due to the sensation felt by overheating., La ventilación de los edificios cumple dos funciones fundamentales: asegura la entrada de aire fresco y limpio, mejorando la calidad del aire en el interior de los edificios y favoreciendo la eliminación de los contaminantes que se encuentran en su interior. Conocer y cuantificar la ventilación de un edificio es el primer paso para un correcto control y definición de la estrategia de uso más adecuada. En este contexto, la simulación por computadora puede jugar un papel fundamental, permitiendo estimar las ganancias y pérdidas de temperatura interna asociadas a cada estrategia, ayudando al usuario y/o diseñador en la elección. La técnica más común para medir las tasas de ventilación se basa en el uso de un gas trazador. En este trabajo se midieron las renovaciones horarias en una casa de interés social utilizando el método del gas trazador y la técnica de la pendiente. Para ello se realizaron cinco pruebas que permitieron evaluar la variabilidad de los resultados. Los resultados se utilizaron como datos de entrada en un modelo de simulación con la ayuda de EnergyPlus 8.6 y DesignBuilder 5.5.2. El valor medio de renovaciones horarias obtenido en las pruebas fue de 1,16 h-1, demostró que el aumento de la tasa de renovación del aire en la residencia, especialmente por la noche, contribuye a mitigar las molestias ocasionadas por sobrecalentamiento., A ventilação dos edifícios desempenha duas funções fundamentais: garante a entrada de ar fresco e limpo melhorando a qualidade do ar no interior dos edifícios e promove a retirada dos poluentes que se encontram no seu interior. Conhecer e quantificar a ventilação de um edifício é o primeiro passo para um correto controle e definição da sua estratégia de utilização mais adequada. Nesse contexto, a simulação computacional pode desempenhar um papel fundamental, permitindo estimar ganhos e perdas de temperatura interna, associados a cada estratégia, auxiliando o usuário e/ou projetista na escolha. A técnica mais comum para medir as taxas de ventilação assenta na utilização de um gás traçador. Neste trabalho mediram-se renovações horárias em uma casa de interesse social através do método do gás traçador e da técnica do declive. Para esse fim foram realizados cinco ensaios, permitindo avaliar a variabilidade dos resultados. Os resultados foram utilizados como dado de entrada num modelo de simulação com auxílio do EnergyPlus 8.6 e do DesignBuilder 5.5.2. O valor médio de renovações horárias obtido nos ensaios foi de 1,16 h-1, demonstrando que o aumento da taxa de renovação de ar na residência, principalmente no período noturno, contribui para mitigação do desconforto por sobreaquecimento.

PurposeThis paper aims to further the discussion on Building Information Modelling (BIM) legal requirements, providing a framework with key energy parameters capable of supporting the Appointing Party in the definition of the Exchange Information Requirements (EIR) for a BIM project appointment. The EIR is described in ISO-19650–1:2018 as a fundamental step in the information delivery cycle.Design/methodology/approachA literature review on the topic of BIM energy analysis was completed to identify current knowledge gaps and support the need for the proposed framework. Afterwards, the framework was established based on the review findings and the authors’ domain knowledge. The applicability of the proposed framework was assessed through a case study, where several energy simulations were performed in three different design stages of the same BIM model.FindingsThis study identified a lack of standards and legislation capable of supporting the Appointing Party in the definition of energy-related BIM requirements. To this end, a new framework is proposed to mediate existing practices, linking prior knowledge with BIM’s new reality. The study showcases the applicability of the framework, identifying that the performance of different energy studies involves distinct Level of Development (LOD) requirements, which in turn have an impact on the modelling time and cost.Originality/valueA BIM framework for the specification of information requirements in energy-related projects was developed to support the Appointing Party. The framework presents appropriate parameters for energy analysis in each design stage, as well as the suitable LOD for the BIM model.

Mould growth on the inner surfaces of building elements is a common pathology found in buildings, resulting not only in the early degradation of the materials but also in the deterioration of the indoor environment. On the other hand, building renovation provides an exceptional opportunity to improve the quality of life of its users. Within this scope it is therefore relevant to understand the effect that different painting solutions may have on mould growth. This work evaluated the mould growth in four kinds of substrates, with different painting systems. The selected case studies were: two “tabique” walls (constructive solution with strong implantation in the built heritage), one with lime mortar and another with lime and cement mortar; and two gypsum plasterboards (a constructive solution that is widely applied in building renovation), a normal and a water repellent. To evaluate the mould growth, two methodologies were adopted: counting the number of colony forming units (CFU) in six sampling periods; and visual inspection through photographic recording, including the quantification of the percentage of "dark pixels". At the end of the test it was established that plasterboard was more favourable to mould growth when compared to “tabique” walls. Moreover, the roughness of the substrates and the sampling location had also significant impact on the results. Received: 2019-2-13Revised: 2019-12-6Accepted: 2020-1-24Online: 2020-5-28Publication: 2020-11-27, O desenvolvimento de fungos nas superfícies dos elementos construtivos é uma das patologias mais habituais no interior dos edifícios, resultando não só na degradação precoce dos materiais, mas, especialmente, na deterioração das condições de habitabilidade. Por outro lado, intervir num edifício, reabilitando-o, é, desde logo, uma oportunidade excecional para melhorar a qualidade de vida dos seus ocupantes. Desta forma, é relevante compreender o eventual efeito inibidor que diferentes soluções de pintura poderão ter no desenvolvimento de fungos. Neste trabalho foi avaliado o desenvolvimento de fungos em quatro tipos de suporte, onde foram aplicados sistemas de pintura com diferentes características. Os suportes selecionados foram: duas paredes de tabique (solução construtiva com forte implantação no património edificado corrente), uma com argamassa à base de cal e outra com argamassa à base de cal e cimento; e duas placas de gesso cartonado (solução construtiva atualmente bastante aplicada em intervenções de reabilitação), uma normal e outra hidrófuga. Para avaliar o desenvolvimento de fungos foram adotadas duas metodologias: a contagem do número de unidades formadoras de colónias (UFC), tendo sido realizadas colheitas em seis momentos; e a inspeção visual através de registo fotográfico, incluindo a quantificação da percentagem de “pixéis negros”. No final do ensaio foi possível concluir que o gesso cartonado é um substrato mais favorável ao desenvolvimento de fungos, quando comparado com as paredes de tabique, e que a rugosidade dos substratos e o local da colheita foram aspetos relevantes para os resultados. Recebido: 2019-2-13Revisto: 2019-12-6Aceite: 2020-1-24Online: 2020-5-28Publicação: 2020-11-27

InfraRed Thermography (IRT) has proven to be a valuable diagnostic tool due to its real-time, remote, and non-destructive operation yielding accurate detection of the position of defect areas in building façade ceramic tiling. Ceramic tiles coating building façades are widely used throughout the world because of their technical and aesthetic characteristics. However, the detachment of ceramic tiles and the water infiltration in deep layers are still common problems. So, this paper proposes active infrared thermography as a thermographic acquisition mode, in contrast to the common use of passive thermography, and segmentation of defect areas and automation in the thermal image processing as added values never before proposed in the ceramic tiling thermographic inspection. For that, specimens of ceramic tiling for building façades were tested under different laboratory conditions, with inserted corks (simulating detachments), and by injecting water into holes drilled in the back surfaces (simulating water infiltration), as defects. Good results have been obtained in all the tests, both in dry and wet conditions in the specimens and for surfaces with homogeneous and heterogeneous surface properties, serving the introduction of this workflow for a first and fast inspection in ceramic tiling building façades. Future research will work with the fine-tuning phase of the methodology by applying it to real case studies. Financiado para publicación en acceso aberto: Universidade de Vigo/CISUG Ministerio de Educación, Cultura y Deporte | Ref. FPU16/03950 Fundação para a Ciência e a Tecnologia | Ref. UIDB/04708/2020

Apesar de não ser um conceito novo, a construção modular tem sido alvo de crescente interesse e investimento nos últimos anos. Os sistemas construtivos modulares em madeira apresentam vantagens económicas e ambientais, pois a madeira é uma matéria-prima natural e localmente disponível, para além de apresentar propriedades térmicas interessantes. Neste contexto, o Projecto BlueWoodenHouse, numa abordagem integrada entre a Ciência e a Indústria, visa, entre outros objetivos, caracterizar as soluções, sistemas e materiais utilizados numa moradia unifamiliar de construção modular em madeira, bem como monitorizar a concentração de CO2 e os parâmetros higrotérmicos da mesma em plena utilização. A moradia tem três ocupantes, três quartos e uma área de 190 m2 . Inicialmente, foi realizado um levantamento e caracterização dos materiais e soluções construtivas utilizados, nomeadamente nas paredes, pavimento e cobertura. Os dados obtidos na monitorização higrotérmica (temperatura e humidade relativa) foram analisados e avaliou-se o conforto térmico interior.

This paper proposes a methodology that combines spatial and temporal deep learning (DL) models applied to data acquired by InfraRed Thermography (IRT). The data were acquired from laboratory specimens that simulate building facades. The spatial DL model (Mask Region-Convolution Neural Network, Mask R-CNN) is used to identify and classify different artificial subsurface defects, whereas the temporal DL model (Gated Recurrent Unit, GRU) is utilized to estimate the depth of each defect, all in an autonomous and automated manner. An F-score average of 92.8 ± 5.4% regarding defect identification and classification, and a root-mean-square error equal to 1 mm in the estimation of defect depth equal to 10 mm as the best defect depth estimation, are obtained with this first application of a combination of spatial and temporal DL models to the IRT inspection of buildings.

Infrared thermography is often used to assess body temperature. It is a useful diagnostic tool for detecting human diseases but, nowadays, is has found a new applicability as an instrument of control during the crisis of the COVID-19 pandemic. Some authors also used it to assess thermal comfort inside buildings. However, some understudied issues still remain regarding the influence on the measurement of the environmental conditions, the position of the subject and the equipment characteristics. This paper attempts to address some of these issues, highlighting that ambient temperature has an impact on image resolution. Additionally, the position of the subject is a key parameter when assessing body temperature, and different equipment deliver different results. (c) 2021 by the authors.

Infrared thermography (IRT) has become a commonly applied non-destructive testing method for assessing building envelopes. Like any diagnosis tool, IRT requires an appropriate experience and principle understanding, mainly when the method is used for quantitative analyses.The challenges of the IRT often deal with the dynamic properties of building partitions.Climatic conditions have a certain variability, and the accumulated energy storage in the building components can affect their temperature as well as the calculated thermal performance. This paper aims to analyze how stationary and dynamic regimes of a quantitative IRT test could impact the measured thermal transmittance of heavy multi-leaf walls. Investigation in two European countries with different climatic conditions are reported. In this way, it is discussed which boundary conditions should be guaranteed to provide reliable information about a building envelope using quantitative IRT. In order to check the quality of the measurements, the heat flux meter (HFM) method was also implemented, following the ISO 9869. The research revealed that it could be possible touse short-lasting tests in the climatic conditions of Southern Europe, while long-term tests should beimplemented in Northern European countries where climatic conditions are less regular. This work was financially supported by UIDB/04708/2020 of the CONSTRUCT-Instituto de I&Dem Estruturas e Construções-and national funds through the FCT/MCTES (PIDDAC). This work was also financed by the Polish National Agency for Academic Exchange (NAWA) under the International Academic Partnership Program within the framework of the grant: E-mobility and sustainable materials and technologies EMMAT(PPI/APM/2018/1/00027)

The water ingress phenomenon in sandwich-structured composites used in the aerospace/aeronautical sector is a current issue. This type of defect can cause in the course of time several other defects at the boundary, such as corrosions, deformations, detachments. In fact, water may change its state of physical matter going towards the freeze–thaw cycle caused by the atmosphere re-entry of, e.g. space probes. In this work, the alveoli of a composite laminate have been filled with water, which was initially transformed into ice. By taking into account, the known quantity of water, the freeze–thaw cycle was simulated by Comsol Multiphysics® software, reproducing exactly the shape of the sandwich as well as the real conditions in which it was subsequently subjected in a climatic chamber. The experimental part consisted of monitoring the front side of the specimen by means of a thermal camera operating into the long-wave infrared spectrum, and by setting both the temperature and the relative humidity of the test chamber according to the values imposed during the numerical simulation step. It was found that the numerical and experimental temperature trends are in good agreement with each other since the model was built by following a physico-chemical point-of-view. It was also seen that the application of the independent component thermography (ICT) technique was able both to retrieve the positions of the defects (i.e. the water inclusions) and to characterize the defects in which a detachment (fabricated between the fibres and the resin) is present; the latter was realized above an inclusion caused by the water ingress. To the best of our knowledge, this is the first time that ICT is applied to satisfy this purpose.

Moisture is one of the major causes of problems in buildings, and it can compromise their performance. Infrared thermography (IRT) is a non-destructive testing technology that can be used to assess the humidification phenomenon and, thus, prevent some of the problems caused by moisture. The images obtained by IRT reflect the thermal patterns of the surface under study and can be evaluated using a quantitative approach, which allows not only the traditional visualization of the thermal patterns but also quantification of surface temperatures and/or their differences. The relevance of this work is related to the discussion of the strengths and weaknesses of several methods to quantitatively assess the humidification phenomenon using IRT. For that purpose, the partial humidification by the bottom surface of a lightweight concrete specimen was considered as a case study. To evaluate the thermal gradients, the evolution of the thermal imaging throughout the measurement period and the definition of the areas particularly affected by moisture, a methodology that included a pre-processing phase for data reduction, followed by a data processing phase, were implemented. In the data processing, different statistical and numerical methods were tested. The results of the statistical descriptive analysis highlighted the time variation of the surface temperature, both when considering the entire specimen and when considering only specific areas. The variability of the temperatures at certain moments of the experiment could be observed in the box-plot representation. The image subtraction proved to be an interesting technique to quantify the temperature differences if the first image was used as reference. A thermal index, TI, was proposed to assess the cooling rate. The index highlighted the initial instant when the effect of moisture on the surface temperature was detectable.

Computing a 2D colour map of average U-values pixel-by-pixel could become a challenging task in terms of complexity and time, especially for entire façades under the influence of anomalies. In a quantitative IRT test, a thermal image with a resolution of 320 × 240 pixels involves 76,800 elements with different TWALL for each instant “t”. This research aims to create a thermographic 2D U-value map for the characterization of heavy walls in a stationary regime. The method was divided into three steps: (i) metrology; (ii) assessment of how mesh discretization affects the image quality by MATLAB; (iii) development of a 2D map by SURFER. The results demonstrated that all 2D maps were a great reproduction of the original image, considering as optimum a TWALL mesh comprised of 1600 elements of 8 × 6 pixels. The automated data-processing method only took 20 min and image quality losses were estimated at 6.65% This work was financially supported by: UID/ECI/04708/2019 - CONSTRUCT - Instituto de I&D em Estruturas e Construç ̃oes funded by national funds through the FCT/MCTES (PIDDAC).

Building Information Modeling (BIM), as a rising technology in the Architecture, Engineering and Construction (AEC) industry, has been applied to various research topics from project planning, structural design, facility management, among others. Furthermore, with the increasing demand for energy efficiency, the AEC industry requires an expeditious energy retrofit of the existing building stock to successfully achieve the 2020 Energy Strategy targets. As such, this article seeks to survey the recent developments in the energy efficiency of buildings, combining energy retrofitting and the technological capabilities of BIM, providing a critical exposition in both engineering and energy domains. The result is a thorough review of the work done by other authors in relevant fields, comprising the entire spectrum from on-site data acquisition, through the generation of Building Energy Models (BEM), data transfer to energy analysis software and, finally, the identification of major issues throughout this process. Additionally, a BIM-based methodology centered on the acquired knowledge is presented. Solutions for as-built data acquisition such as laser scanning and infrared thermography, and on-site energy tests that benefit the acquisition of energy-related data are explored. The most predominant BIM software regarding not only energy analysis but also model development is examined. In addition, interoperability restrictions between BIM and energy analysis software are addressed using the Industry Foundation Classes (IFC) and Green Building Extensible Markup Language (gbXML) schemes. Lastly, the article argues the future innovations in this subject, predicting future trends and challenges for the industry.

The increasing energy concerns across the European Union enhanced the importance of buildings ventilation and pointed out the reduction of energy for ventilation as one of the targets. The measurement of ventilation and leakage rates are therefore necessary to understand buildings performance, especially in mild climate countries where often dwellings ventilation is adventitious and highly influenced by user behaviour. In mild climate countries, natural ventilation is the most common strategy. The air movement is therefore a combined result of pressure differences produced by wind and buoyancy forces, which are both time-dependent. Under these circumstances, one-time measurements of the air change rate, made over short periods, may not be an accurate indicator. An experimental campaign for the evaluation of the air change rate in a Portuguese dwelling was conducted over a period of two months. During this period, tracer gas measurements were performed in two compartments: (R1) living room; and (R2) bedroom. In each, two different boundary conditions were tested: (i) door closed; and (ii) door opened. A total of 132 tests were carried out. The decay technique was used for the quantification of the air change rate. Simultaneously, indoor and outdoor conditions were continuously monitored. The results highlighted the importance of performing several measurements as some variability was found, especially for the open door scenarios. Moreover, the importance of wind speed was also confirmed as the main trigger mechanism in naturally ventilated buildings, especially in the mid-season period where the indoor/outdoor temperature difference is not significant.

The air change rate per hour (ACH) inside a dwelling depends on its envelope air-tightness, ventilation devices and weather conditions. However, the occupant behaviour of residential buildings in mild climates is a key factor for the resulting ACH, influencing the indoor air quality and thermal comfort. This study was based in a one-year measurement campaign aiming at the assessment of the influence of occupants on the ventilation conditions of a dwelling located in Porto, Portugal. The master bedroom was monitored using temperature, relative humidity and CO2 sensors and air-tightness was evaluated with blower-door tests. In addition, surveys were also carried out where the occupants registered these actions and their occupation in the studied room. In this study, it was found that the main actions performed by occupants with influence in the ACH were related with windows handling and air grill extraction vents regulation. The measurements allowed to define behavioural typical patterns. The results include the typical CO2 concentration profiles in the main room and its variation in function of occupant behaviour. It was found that opening the air grill extraction vents could vary the total ACH up to 92%. Opening windows at night could increase the total ACH up to 435%. Before the morning window opening the minimum ACH obtained was 0.37h-1 and the action of morning window opening lead to an average ACH around 4 h-1.

Moisture in building materials and components is a key aspect to be considered when assessing buildings performance, as it may influence their durability and mechanical resistance, thermal comfort and indoor air quality and buildings energy efficiency. Therefore, studying the humidification phenomena is of major relevance. The presence of moisture in building materials/components is related to temperature variations. The surface temperature of the object can be measured using infrared thermography (IRT), a non-destructive technology to assess the buildings behaviour. Hence, it is important to understand its applicability to assess moisture related phenomena. In the present study an analysis of the humidification phenomena using IRT was intended. Lightweight concrete specimens were used and tests were carried out under stable hygrothermal conditions. Two different humidification conditions were assessed: (1) partial humidification by the specimens’ bottom surface; (2) partial humidification by the specimens’ top surface. Thermal images were taken periodically during 24 hours. Both qualitative and quantitative analysis of the results was performed. The results pointed that assessing the humidification phenomena using IRT is possible under stable conditions. The boundary conditions for the humidification process affected the results interpretation as it was easier to detect moisture when the surface under study was in direct contact with liquid water (partial humidification by the specimens’ bottom surface). In this case clearer surface temperature differences could be found between the moist and the dry areas, which appear sooner in time. The surface temperature decrease was marked near the bottom during humidification by the bottom and near the top during humidification by the top, highlighting the effect of evaporation at the surface.

Energy consumption is one of the major concerns of European citizens and governments. In the EU, buildings use 40% of total energy consumption and generate 36% of greenhouse gases. Therefore, buildings energy efficiency must be optimized, which requires, among others, minimizing infiltrations through the envelope. The measurement of the air leakages through a building envelope is usually carried out by means of the fan pressurization method (Blower Door Test). Although useful for assessing the airtightness of buildings no information is obtained regarding the air leakage pathways. For that, other techniques such as infrared thermography (IRT) can be used. This work presents the results of an experimental campaign that aimed to assess the applicability of IRT to detected air leakage through the roller shutter handle and the window frame of a room. A quantitative approach for results analysis was implemented and the contribution for airtightness of both roller shutter handle and window frame was also evaluated using the Blower Door Test. It was possible to conclude that the window frame had a larger contribution to the air flow rate than the roller shutter handle (109.4 m3/h and 21.7 m3/h, at a pressure difference of 50 Pa). Qualitative analysis of the thermal images indicated that a colder area near the leakage point can be detected and that it grows with the increase of the pressure difference. The quantitative approach showed that a stabilization of the surface temperature close to the value of the outdoor temperature occurred and the relative differences are around 15% both for the window frame and the roller shutter handle. It also showed that, in most cases, the first pressure step (ΔP = 25 Pa) is responsible for about 60% of the differences in the superficial temperature. A good correlation was found between the proposed Pressurization Thermal Index and the temperature gradient between the exterior air temperature and the initial superficial temperature (ranging from 0.74 to 0.82).

The importance of a good indoor environment for peoples' health and wellbeing is nowadays clearly established. Besides enhancing the wellbeing of building occupants and helping decrease the occurrence of building related illness, a good indoor environment can also lead to a decrease in worker complaints and absenteeism. This paper presents the results of a three-month monitoring campaign where the thermal comfort of a toll station was evaluated, including the main room and the cabins. The physical parameters required for the assessment of both global and local thermal comfort were measured and the results were compared with the thermal perception of the occupants, which was collected through questionnaires. The indoor environmental quality in the main room was better than in the cabins and a mismatch between the PMV index and the occupants thermal sensation was identified.

Risk prevention must be based on a correct and permanent risk assessment in the work as a core activity of health and safety services. In several activities workers are not aware of the risks they are exposed to, namely when it is not their common work. The main objective of this study was to evaluate the risk of exposure of technicians in a research laboratory to biological and chemical agents. For this purpose, indoor air of three rooms with different characteristics was sampled from February to July (6 campaigns). For biological agents both passive and active methodologies were applied. The chemical and physical parameters were also measured in each campaign. The fungus colonies forming units (CFU) in the passive sampling and bacteria CFU in the active sampling were below the determination range for each method. The active sampling of fungus revealed a high concentration in two rooms, in agreement with the hygrothermal conditions that were measured. In these rooms, the fungus amount was higher than the reported for compliance established by national legislation for indoor air quality. VOCs concentrations were also above the acceptable level and thus some preventive measures regarding ventilation should be implemented.

Moisture is one of the major causes of building decay, compromising the indoor air quality and the durability of building components. Infrared thermography is a non-destructive technique that can be used to prevent damage caused by the presence of water. In this study, the potential of Principal Component Analysis (PCA) was assessed as a quantitative technique for processing the thermal images captured during 24 hours of water absorption by a lightweight concrete specimen. PCA showed that the first principal component is the one that better explains the phenomenon. The initial instant was the most interesting to identify the water level in the sample and the final instant allowed defining the first 8h as the most relevant.

Infrared thermography (IRT) is a non-destructive testing technology used to assess the performance of buildings. As a diagnosis tool for retrofit and conservation of buildings it helps understanding the anomalies by allowing "seeing" their causes in a non-invasive manner. However, in most cases, the interpretation of the results (thermal images) is mainly qualitative, restraining and, eventually, pointing to incorrect conclusions. Using numerical tools that contribute to the quantitative interpretation of IRT applications is therefore a step forward in this field. The main objective of this work is the evaluation of heat transfer in humidification phenomena by comparing the results of 2D hygrothermal simulation with thermal images. Thermal images were taken to a lightweight concrete specimen during a 24-hours partial immersion period. The humidification of the specimen was simulated using WUFI 2D. The best way to deal with the liquid water level in contact with the bottom of the specimen was deeply analysed. The comparison of the simulation with the results of IRT showed that the program tends to overestimate the phenomena of heat transfer (water rise and evaporation on the surface), as the water level reached in the simulation was consistently higher than the one obtained in the thermal images.