Reviews the ventilation requirements for residential buildings and the recently discovered contaminants of indoor air which will have an influence on the required ventilation rates. Describes methods of measuring air leakage and the rate of air infiltration. Cites work aimed at finding the correlation between air leakage and air infiltration. Outlines the role of heat recovery devices and recommends areas of further research. An appendix reports on a Canadian Mortgage and Housing Association seminar "Controlled ventilation with exhaust air heat recovery for Canadian housing".
Considers that air change measurement by means of tracer gas is the best way of measuring natural air infiltration in buildings. In some cases the method can be useful for measuring the ventilating air rate in mechanical systems asno interference with the system is required by the method. Deals with the theory of the method, the handling and measurement of different gases, cost of gas and instruments. Concludes by saying that only very simple instrumentation is required for most of the measurements with satisfactory accuracy.
Reports measurements of radon daughters in air. The daughters were collected on filters for different lengths of time. A silicon semiconductor detector and the etch foil technique were used to measure the alpha particles from the radon daughters. Finds that alpha particle concentrations in living rooms have the same variation with time as outdoors.
Presents a new method for determining the airborne concentrations of RaA, RaB and RaC in atmospheres contaminated with radon-222. The method employs alpha spectroscopy to measure the count rates of RaA and RaC' present on a membrane filter sample at two post-sampling times. The individual air concentrations and the statistical variances associated with each may then be calculated from the equations given. Presents theoretical and experimental comparisons which indicate the improved accuracy of the spectroscopic method over methods previously available.
Discusses the tracer dilution method for measuring air change rates. The technique entails introducing small amounts of tracer gas into a building and measuring the rate of change in tracer concentration. Describes the method and compares different tracer gases. Outline ways of obtaining an estimate of the air infiltration from experimental data. An appendix discusses the errors in the procedure.
Reviews the state of the art in the measurement of ventilation and air infiltration. Considers tracer gas techniques and discusses some of the tracer gases used as well as some of the potential sources of error. Also discusses fan pressurization-evacuation procedures for measuring building tightness and compares fan and tracer measurements. Discusses the ASHRAE crack method.
Describes use of a radioactive tracer for measuring ventilation rates. Finds krypton 85 is the most suitable gas although xenon 133 and argon 41 have been used. Mentions various studies using radioactive tracers made in both France and England. Suggests commercial sources for krypton 85.
Describes test apparatus and method of testing windows for air leakage. This standard has been adopted by the following countries :- Austria, Belgium, Denmark, France, Italy, Netherlands, Spain, Switzerland and United Kingdom. It is available in English, French or German.
Describes the two major methods of measuring air leakage in buildings; the tracer gas method and the pressure method. The three ways of using tracer gas are with decreasing gas concentration, constant gas concentration, and with constant gasrelease. In Sweden nitrous oxide is normally used. The results of the tracer gas method may depend on the weather at the time of measurement. The pressure method is fast and accurate, but only gives the total leakage through the building. Local differences can be detected by use of infrared photography.
Discusses use of tracer gases for the measurement of natural ventilation rates States advantages of using radio isotopes are increased speed and sensitivity. Gives expressions for calculating air change rates using radio isotopes from thedecrease in signal. Suggests use of krypton 85 or Xenon 133 as tracers. Discusses errors in the method. Reports study of air quality in a naturally ventilated building in Yakutsk. Air change rates, temperatures and concentrations of carbon monoxide were measured in kitchens with gas stoves.
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