Submitted by Maria.Kapsalaki on Wed, 04/17/2019 - 15:53
The air renovation of a building should be controlled in order to ensure a proper level of indoor air quality while minimize heat losses. It is a crucial point for the future energy efficiency goals. However, air infiltration rate in buildings is a complex parameter which is influenced by several boundary conditions. Although a detailed dynamic analysis could be used to properly characterize the phenomenon, estimated values can be obtained from experimental methods, as Blower Door test and gas concentration-based approaches.
Submitted by Maria.Kapsalaki on Mon, 04/15/2019 - 16:12
The air infiltration of a building, which fundamentally depends on its airtightness, can be a significant contributor to its heat loss. It can also be affected by other factors such as external terrain, leakage distribution, sheltering factor and environmental conditions. The infiltration rate of a detached UK house was monitored for 2 months in early 2018 using constant concentration and decay tracer gas methods under various temperature and wind conditions.
Submitted by Maria.Kapsalaki on Mon, 04/15/2019 - 11:40
Amid the contaminant issues, air pollution has awakened more interest due to its potential health risk and its direct effect on human productivity. The overall indoor environment quality depends on the contribution of both the indoor and the outdoor air quality. The outdoor air pollutants penetrate indoor environments through mechanical and natural ventilation as well as by infiltrations through cracks and leaks in building’s envelope. The interaction between the indoor and outdoor air may be studied by the air exchange rate.
Submitted by Maria.Kapsalaki on Mon, 11/16/2015 - 17:22
Interior wooden surfaces have the capacity to buffer the maxima and minima of relative humidity (RH) indoors. Especially in high performance buildings, where high airtightness levels as well as high indoor air quality (IAQ) are required, there is great potential for energy savings by reducing the mechanical ventilation demand. The last decade, the moisture buffer phenomena has been widely researched. Relevant findings showed that the moisture buffering effect is reduced when the ventilation rates increase.
Submitted by Maria.Kapsalaki on Thu, 05/28/2015 - 12:55
We propose a new approach for measuring air infiltration rates in buildings. The method belongs to the class of tracer gas techniques but, unlike conventional CO2 based methods that assume the outdoor ambient CO2 concentration is constant, the proposed method recognizes that photosynthesis and respiration cycle of plants and processes associated with fuel combustion produce daily, quasi-periodic, variations in the ambient CO2 concentrations.
Submitted by Maria.Kapsalaki on Thu, 04/03/2014 - 15:38
The report discusses the need for a proven method of measuring air infiltration rates in large enclosures in order to assess the need for and effectiveness of energy saving measures. The object of the research is to develop such a proven method. Some
Submitted by Maria.Kapsalaki on Wed, 11/06/2013 - 09:18
The existence of air leakages in a building has been very clearly stated as an important reason for energy loss. The decrease in the efficiency of the mechanical ventilation has also been clarified. The global demand for achieving nearly zero-energy buildings makes the uncontrolled leakage paths even more undesired. Despite the fact that steady state measurements of in- and exfiltration rates offer a simple and easy way of estimating the airtightness level of an eclosure, a supplement to those methods might be imposed.
Submitted by Maria.Kapsalaki on Tue, 11/05/2013 - 14:25
Accidental dispersion of toxic gas clouds may occur around industrial platforms or during hazardous materials transportation. In case of such a toxic risk, the best protection strategy is to remain inside a building and seek refuge in an airtight room identified as “shelter” until the toxic cloud has finally been swept off. This strategy called “passive shelter-in-place” also includes obstructing all external openings and turning off all mechanical ventilation systems
Submitted by Maria.Kapsalaki on Tue, 11/05/2013 - 13:42
LBNL Residential Diagnostics Database (ResDB) contains blower door measurements and other diagnostic test results of homes in United States. Of these, approximately 134,000 single-family detached homes have sufficient information for the analysis of air leakage in relation to a number of housing characteristics. We performed regression analysis to consider the correlation between normalized leakage and a number of explanatory variables: IECC climate zone, floor area, height, year built, foundation type, duct location, and other housing characteristics.
Submitted by Maria.Kapsalaki on Fri, 11/01/2013 - 11:44
Accidental releases occurring in industrial platforms or during transportation of hazardous materials can entail the dispersion of toxic gas clouds. In case of such an event, the best protection strategy for people is to identify a shelter in a nearby building and stay in this room until the toxic cloud has finally been swept off.