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Supplemental Material, sj-pdf-1-lrt-10.1177_14771535211046521 for Lighting conditions in physiotherapy centres: A comparative field study by L Zaniboni, M Sarey Khanie, G Pernigotto, J Toftum, A Gasparella and BW Olesen in Lighting Research & Technology

The threat of a new pandemic has forced the WHO to publish preparedness plans. Although WHO recognized the effect of airborne transmission of the causative agent, they did not attempt to include feasible measures for indoor environmental control as yet. The efficacy of indoor humidity control compared to other air related measures such as ultra violet irradiation, portable HEPA filtering and increased ventilation rate has been studied in order to slow down infection spread. This study is limited to homes. A combination of the Wells-Riley equation and the Nazaroff's equation was used to compute the effect of each measure in order to decrease the infection risk. An increase of ventilation and the use of portable HEPA filters were not effective. Although ultra violet radiation appeared more effective than humidification control, the latter is most feasible.

The objective of this research was to study the effects of a moderate temperature drift on human thermal comfort, physiological responses, productivity and performance. A dynamic thermophysiological model was used to examine the possibility of simulating human thermal responses and thermal comfort under moderate transient conditions. To examine the influence of a moderate temperature ramp, a climate room set-up with experimental subjects was used. Eight subjects visited the climate room on two occasions: 1) exposure to a transient condition (a moderate temperature ramp) and 2) a steady temperature corresponding with a neutral thermal sensation (control situation). During the experiments both physiological responses and thermal sensation were measured. Productivity and performance were assessed with a ‘Remote Performance Measurement’ (RPM) method. Physiological and thermal sensation data indicate significant differences between the transient condition and the control situation. Productivity and performance tests show no significant changes between the two situations. Simulations obtained with the thermophysiological model were in good agreement with the measurements. Possible improvements of the performance and productivity tests and the thermophysiological model will be discussed.

Thermophysiological models may provide an alternative solution to predict thermal comfort in non-uniform thermal environments. In this study a thermophysiological model based on the model of Fiala was used. The purpose of the study was to validate the model through a laboratory study with test subjects who were exposed to a non-uniform thermal environment. During the experiments both the physiological response and thermal sensation ofthe subjects were measured. The physiological response and thermal sensation predicted by the thermophysiological model were compared to the measurement results. The results showed that the model predicts the mean skin temperature well (root mean squared deviation 0.95K). However, the predicted core temperature was too low «36°C) for subjects with a high fat percentage (>20%). The bias between predicted and measured thermal sensation was large(root mean squared deviation 0.95). Possible improvements to the model are discussed.

This paper presents the pre-investigation for a sensitivity analysis of design and use parameters of an operating room on the spread of airborne bacteria. The sensitivity analysis will use CFD (computational fluid dynamics) simulations to evaluate the airflow and spread of bacteria in a room. The pre-investigation consists of a grid study and an evaluation of two different methods of performing the sensitivity analysis.

Office buildings with HVAC systems consistently report Sick Building Symptoms that are derived from microbial growth. We used the HACCP methodology to find the main critical control points (CCPs) for microbial management of HVAC systems in temperate climates. Desk research revealed relative humidity (RH) as a main limiting factor, with fungi needing at least 65% RH and bacteria 91%. Particle deposition inside the HVAC system provides the necessary growth substrate. Filters exposed to outdoor climatic conditions are vulnerable to fungal growth 80% of the time in a year, making them the first main CCP. High RH is also found at the cooling section (the 2nd main CCP). Particle deposition is highest in bends of the ductwork (3rd main CCP). We recommend microbial monitoring and controlling of the humidity level at these 3 CCPs to manage microbial growth in HVAC systems.

Since the Energy Performance for Buildings Directive (EPBD) was accepted and implemented over the course of the last years, buildings are audited energetically to receive the necessary construction licenses. This augmented the already high attention to research on innovative (passive) energy-saving system concepts even further. Previous research suggests that, although the effect of commissioning can be significant, specific fan power is the most important factor influencing the energetic viability of mechanically driven night ventilation as an active cooling replacement. This parameter should thus be the central point of focus during the design process. In this paper, we present an analysis of the effect of detailed convective heat transfer modeling on the predicted performance, in order to determine the level of detail needed to assess feasibility of this kind of system in early design phases. Results indicate that the effect amounts to 20-50% of the predicted performance and therefore cannot be neglected. It is within the range of effect of the dominant parameter, specific fan power. In light of these results, it is suggested that detailed convective heat transfer coefficient modeling is taken into account whenever forced convection due to large volume flow is introduced.

Because of high computational costs of computational fluid dynamics multi-zone energy simulation is currently appraised. Yet, the use of empirical correlations to predict interior convective heat transfer (CHT) limits the reliability of building comfort and energy analysis. As most of these convection algorithms depend, partially, on the temperature difference between the concerned surface and the air, the influence of the modeling of incoming direct solar radiation is studied. Simulations of summer comfort in a night cooled office room in Belgium are carried out in TRNSYS using different convection algorithms and four methods to model the distribution of solar radiation. This work demonstrates that the influence of the modeling of incoming solar radiation on the predicted thermal comfort and energy demand is inferior to the choice of the CHT correlations. Therefore, before putting considerable effort in the modeling of direct solar radiation, an accurate approach of the CHT is regarded necessary.

Most of the existing ventilation standards are drafted in a rather prescriptive way. Growing focus on the implementation of rational energy use however, introduces an urgent need for more performance-based criteria. Optimization of energy consumption obviously encompasses minimization of ventilation airflow rates. Comfort, on the other hand, should not be reduced because of these actions. To implement this in a legal figure, one can appeal to the principle of equivalence. This principle states that all systems achieving equivalent performance to that of the systems described in the standard are acceptable. Better yet, a new standard can be devised, imposing a reference performance rather than a reference system. This avoids all discussion about the way the reference system’s performance should be interpreted. Nevertheless, practical implementation of a standard will require the definition of sizing guidelines for design purposes. The method presented in this paper is a simplified approximation of the airflow network in a building. It is conceived as a sizing guideline for natural ventilation systems in the context of a national ventilation standard. Supply, internal and exhaust resistances are the main parameters, next to overall building airtightness. These parameters are system independent and allow to describe a large scale of possible buildings. Five different dwellings, with different typologies, representative for the Flemish building stock, were evaluated for this purpose. The predicted airflow and indoor air quality are compared to that predicted by a detailed multi-zone model and acceptable agreement is found. This yields the conclusion that, for the implementation of a performance-based ventilation standard, straight forward calculation methods for sizing guidelines can be incorporated in the standard.