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Abstract: Microclimatic conditions were recorded in an Italian school and Fanger's indexes PMV and PPD were calculated under different conditions. Students' sensations were investigated four times by means of two surveys, one related to actual microclimatic conditions and one on overall satisfaction, interaction occupant-building and reactions to discomfort. Pupils' classroom position was considered to look for possible influence on thermal comfort: a difference emerged from PMV and the survey, but the results obtained from the two approaches differ for both the entity of discomfort and its distribution within each classroom. Innovative multivariate nonparametric statistical techniques were applied to compare and rank the classrooms in accordance with students' subjective perceptions; a global ranking has been also calculated, considering thermal and visual comfort and air quality. Comparing pupil-sensation-based ranking with environmental parameters no clear correspondence was found, except for mid-season, where PMV, CO2 concentration and desk illuminance were similar in all the classrooms. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a field monitoring study of three medical wards at Padua General Hospital (Orthopaedics, Internal Medicine and Paediatrics), based on measurements of indoor conditions and on a survey of patient and medical staff perceptions. Microclimatic conditions were measured over an extended period using data loggers with a time step of 5 min. Maximum in-patient room temperatures exceeded 29 °C while mean values were around 26–27 °C. Generally, microclimatic conditions differed between in-patient and staff rooms. Spot and long-term monitoring was used to calculate PMV profiles which were compared to thermal comfort showing non uniform correspondence among wards and their occupants. Innovative statistical nonparametric methods were applied to analyse the survey, comparing the wards from both patient and staff points of view. Staff complained mostly about lack of privacy, room size, amount of common areas, poor air quality and acoustic discomfort, with significant differences between wards in relation to levels of satisfaction with building-related aspects. Patients, on the other hand, were more satisfied with both building-related aspects and indoor conditions than medical staff. Such a global assessment could easily be used, for example, to rank the necessity or the priority of changes or improvements to buildings as well as determine the most important features, both individually and globally, to be taken into consideration. [Copyright &y& Elsevier]

Abstract: In prehistoric times man wore furs of animals to protect himself from the cold. Successively over the centuries clothing has become also a tool to distinguish ourselves in society. Clothing has in addition an important impact on people''s perception of the indoor environment. Clothing behaviour has been analysed by investigating the external and indoor parameters that motivate people''s choice of clothing. Based on two existing databases, two types of buildings have been investigated: air-conditioned and naturally ventilated (NV) buildings. The impact of outdoor temperature on people''s clothing selection has been considered. The outdoor temperature at 6a.m. seems to affect people''s choice of clothes the most. Gender does not significantly affect the selection of clothing insulation. Latitude has also been investigated and a good correlation has been found between clothing insulation and external temperature in the ranges 20°–40° and −20° to −40° for NV buildings. Indoor air temperature does not seem to influence the clothing choice early in the morning but it does seem to influence the change of clothing during the day, if this is authorized, in workplaces in NV buildings. Such action can be termed “clothing adjustment” during the day. Some computer simulations on a test reference year have been carried out for a typical air-conditioned office to analyse a person''s comfort when wearing different clothes. It is possible to see that in air-conditioned buildings a variation of 0.1clo is sufficient to change totally the comfort evaluation. It is evident that further studies are needed in this field. [Copyright &y& Elsevier]

Abstract: There is a rising interest in heating and cooling systems based on renewable energy sources. Air heating or cooling with earth-to-air heat exchangers (EAHE) is one approach for reducing ventilation heat losses and improving thermal comfort in buildings. A literature research was performed in order to analyze the design, characteristics of earth-to-air heat exchangers and whether they could be coupled with HVAC system coupling. A range of projects was compared in order to collect and summarize design suggestions. [Copyright &y& Elsevier]

Abstract: Several models are available in literature to simulate ground heat exchangers. In this paper an approach based on electrical analogy is presented, for this reason named CaRM (CApacity Resistance Model). In some cases several information are needed during design: both the borehole and the surrounding ground are affected by thermal exchange. The model here presented allows to consider the fluid flow pattern along the classical vertical ground heat exchangers as a single U-tube, a double U-tube or coaxial pipes. Besides, ground temperature at different distances from borehole are calculated, taking into account also the thermal interference between more boreholes. Starting from the supply temperature to the heat exchanger, the outlet fluid temperature is calculated and the ground temperature in each node, step by step. The model has been validated by means of a commercial software based on the finite differences method. Further comparisons have been carried out against data from a ground thermal response test and from the survey of an office building equipped with a ground coupled heat pump and vertical double U-tube heat exchangers. The agreement of results validates the model here presented. [Copyright &y& Elsevier]