Treats investigations in office building where 1) flow rates of supply air, return air and ventilation between main office area and adjacent rooms were measured with an anemometer. Return air rates remained constant but ventilation rates varied widely during measurement periods. 2) CO2 was used as tracer gas to determine ventilation rates in offices. Calculates alterations in gas concentrations in rooms adjacent to stairwell and changes in outdoor air concentrations. During air conditioning, ventilation rates in the room were 4-5 room air changer per hour.
Reports the results of three programmes of measurements of ventilation carried out in one-family houses, which in most cases were of the 'council house' type. The first programme measured ventilation rates using tracer gasin two houses room by room. Wind speed and direction were recorded but no general relation between ventilation and wind was found. The second measured ventilation rate in individual rooms in a house under six different wind conditions. The third measured ventilation rates in three identical homes.
Treats importance of keeping uncontrolled ventilation to a minimum in buildings equipped with balanced ventilation. Provides theoretical and experimental description of leakage of air past windows. Includes comparison between standards of different countries. Discusses effect on building ventilation of variations of wind and outdoor temperature. Considers in conclusion measurement of air flows between rooms in a building. Describes development of tracer gas method based on computer-assisted evaluation.
Describes technique for measuring the volume of air leaving a house through the loft. Two tracer gases are used; nitrous oxide is released in the house and carbon dioxide in the loft. The mean concentration of N2O in the loft gives the volume of house air infiltrating the loft: and the mean concentration of CO2 gives the ventilation rate of the loft itself.< Gives two examples of the use of this technique and gives loft ventilation rate as a function of wind speed for one house.
Presents theoretical model which represents a technique of correlating the easily performed pressurization measurement with the more difficult tracer gas technique. The neutral pressure level is explicitly included to estimate the distribution of openings around the building envelope. Describes model in detail and its application to a number of houses in New Jersey and California.
Presents results of a survey of natural infiltration rates in 2 identical modern homes-one gas fuelled and one electric-over aperiod of a year. Infiltration rates were determined by releasing tracer gas, usually ethane, into the main return duct and measuring concentration every half hour. Discusses results and dependence of infiltration rates on wind speed and direction. Gives preliminary result that wind probably exerts agreater effect on infiltration than any other variable.
Reports measurements of ventilation rates made in a nine-story office building. Two methods were used; tracer gas decay rate using sulphur hexafluoride and a direct method when air flow rates through roof vents and exhaust units were measured. Gives summary of results and finds good agreement between the two methods.
Describes a method for the investigation of ventilation rate in mechanically ventilated closed rooms. The room air is labelled with a radioactive isotope and the ventilation rate inferred from the reduction in radioactivity found by repeated sampling at different locations . Notes the results apply only when the room air is well mixed. Defines a parameter, the "ventilation factor" which describes the variation in ventilation rate. Gives examples of the use of this method.
Describes methods of measuring the air tightness of whole buildings. Outlines three tracer gas methods; constant concentration; decreasing concentration and constant emission. Describes pressurisation method. Describes measuring equipment and test procedure and discusses calculation of ventilation rateand error magnitudes. Gives brief summary of measured results and an appendix contains a print-out of data on the airtightness of houses.
Describes the importance and purpose of measurements of air infiltration. Discusses methods of measuring air-change-rate and the range of measurements. Describes test method and gives preliminary results of practical tests made in living rooms during the winter of 1975/76. Results indicate that more detailed and comprehensive tests are necessary to obtain valid data for heat loss due to air infiltration in rooms and buildings and dependence of air-change-rates on year of construction and type of building.
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