Ventilation has a considerable influence on both the indoor air quality and energy consumption of buildings. Three parameters can be identified which are of key importance in the assessment of ventilation behaviour: air change rate, interzonal air flows, air leakage characteristics. This paper describes measurement techniques which enable these parameters to be evaluated. The listof techniques presented is not exhaustive and the descriptions given are not particularly detailed.
Describes experiments to measure the ventilation rates of two small open-plan factories, one typical of current design and one designed to be more energy efficient, with increased levels of insulation and a tighter method of construction. Air leakage rates were measured using the Watson House Leakage Tester, and ventilation rates were monitored by the Watson House Autovent System. The problems involved are described, and how they were overcome in this case.
Describes a reasonably accurate method for estimating air infiltration for engineers or energy auditors who are not specially trained in infiltration research. The method requires two steps: field measurement of the building properties, and calculation of the infiltration from weather data and themeasured properties. Fan pressurization techniques are described and how to use them to measure the air tightness of the building envelope, and the procedures required to make infiltration predictions with the Lawrence Berkeley Laboratory infiltration model.
This study used a constant concentration tracer gas measurement system to measure the air infiltration rate of three modules simulating residential buildings in Canada. The results obtained were compared with computer predictions.
Large, multicelled and naturally ventilated buildings pose many inherent problems for the measurement of overall infiltration rates using tracer gases. Considering a single tracer gas decay technique, the most obvious problems are: (a) local variations in infiltration, (b) imperfect internal mixing of the air, and (c) practical difficulties in distributing (ie, seeding) the tracer gas and subsequently obtaining air samples.
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