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The indoor air quality is very important for the well-being of occupants, especially in the case of young babies. This research focuses on the air quality of the surrounding air inside a crib with sleeping infants. To study the effects of different sleeping positions of the baby with in the crib a measurement setup was created in the laboratory. The breathing of an infant was simulated by means of a baby doll with air supply mixed with CO2 and measured at different sensor locations for different sleeping positions.

The estimation of low-rise, residential building infiltration rates using envelope airtightness values from whole building fan pressurization tests has been the subject of much interest and research for several decades, constituting a major topic of discussion during the early years of the AIVC. A number of empirical and model-based methods were developed, with their predictive accuracy evaluated in field studies around the world.

The ventilative cooling by natural ventilation is important technology for the buildings in urban area for the sake of energy saving and BCP (Business Continuity Plan). In fact, a large number of high-rise buildings in urban area in Japanese metropolises are equipped with natural ventilation apparatus such as openings and chimneys or shafts.

Outdoor air change qualifies the air that enters into the buildings. The outdoor air moves freely along the urban mesh favoured by the wind forces and stresses. Buildings, trees and other constructions alter the natural air flow pattern inside the cities, creating stagnated air masses in those wind-protected regions. Some outdoor spaces such as light shafts and confined light shafts inhibit the correct exchange of the stagnated air with fresh air coming from the outskirts and suburban areas. 

The work presented is the continuation of the research on the probabilistic modelling of air infiltration carried out by the author over many years. The approach has consisted in considering uncertainties coupled to the climatic/environmental input data to the physical models, or to the threshold criteria for a good performance. The concept of risk/reliability evaluation of building/environment system performance was proposed and exemplified for the air exchange model.  

The opening of windows can lead to high energy losses in wintertime, especially in nearly zero-energy buildings. But can reduce overheating significantly in summertime. Therefore, window use models have been created in the past to assess the energy use and thermal comfort in residential buildings. The models are mostly based on weather-variables. However, a recent study (Verbruggen, Janssens, et al. 2018) indicated that these models were not able to accurately predict the window use in wintertime. For that reason, an occupancy and activity based model was developed.

A ventilation performance report is mandatory for every new residential building in Flanders, for building permits issued since January, 1st 2016. This means that the features of the ventilation system as installed in the dwelling must be reported and that, in the EPB-report of the dwelling, these data must be used to justify the energy performance of the ventilation system. 

To enhance the properly functioning of the ventilation systems, a ventilation preliminary design has to be made before the physical building process is started. 

Studies in the Netherlands show that ventilation systems of dwellings don’t comply with building regulations. The main shortcoming is insufficient ventilation. This applies to both the house as a whole as to individual rooms. Ventilation systems produce too much noise, for example due to the lack of adequate silencers, the location of the ventilation unit and the dimensions of the air ducts.  Because ventilation systems make so much noise when operating at high flow, the ventilation is often only set to the lowest speed (van Dijken, 2011).

The measurement of natural airflows is practically challenging. Driving forces that induce natural airflows are characterized by low pressure differences. Conventional airflow-meters would introduce pressure drops, which can significantly affect the flow pattern. Besides, the measurement of the flow crossing a window is difficult to implement and poorly reliable. Thus, indirect methods called tracer gas methods are widely used to bypass these difficulties, as they do not interfere with the flow pattern.

Building airtightness requirements are becoming more and more common in Europe (Leprince, Carrié, & Kapsalaki, 2017). However, airtight buildings require an efficient ventilation system to ensure good indoor air quality. In France, the inspection of ventilation system (Jobert, 2012) has revealed many noncompliance. They are mainly due to bad conception, poor implementation, and lack of maintenance. This often leads to reduced ventilation flowrates and poor indoor air quality. Leaky ductwork is one of the reasons for this noncompliance.