Investigates the generation of pollutants from unvented convective and radiant kerosene heaters in a residence over a 3 month period. The measured concentrations of carbon monoxide were low. However, under the conditions of use which were studied concentrations of SO2, NO, NO2, and CO2 reached or exceeded levels recommended for indoor air. Further, it was demonstrated that using a semi-open door to provide ventilation did not reduce concentrations of pollutants to acceptable levels.
Compares the air change rates measured using the decay method with several different tracer gases. The tracer gas measurements were conducted in atightly sealed room where constant air leakage rates, ranging from 0.05 to 1 air change per hour could be maintained using an exhaust fan. The tracer gases investigated were CH4, CO, CO2, N2O and SF6. The agreement between tracer gas measurements and measured flow rates of the exhaust fan was very good for CH4, CO and N2O.
Shows the results of a study of the effects of turbulence upon ventilation. Controlled fluctuating air flows were directed upon openings in the side of acube simulating a building. The relationship between the turbulent characteristics of the air flow and the ventilation rate in the building modeare examined. Mean windspeed and the turbulent velocity and intensity of the air flow were measured with a thermocoupled anemometer. Resulting ventilation rates were measured by means of tracer gas decay, using CO2 as the tracer and an infra red analyser to monitor the decrease in concentration.
Carries out measurements of the air infiltration rate of 3 large single cell buildings using the tracer dilution method. The purpose is to determine whether or not there are any special difficulties in using the tracer dilution method in this type of building, prior to emabarking on a more substantial measurement program. Uses nitrous oxide and sulphur hexafluoride as tracers. Finds both to be satisfactory, but concludes that SF6 in conjunction with a portable gas chromatograph performs more reliably when used for on-site measurements.
A major pathway for loss of conditioned air in east Tennessee homes with externally located HVAC systems is leakage in the ductwork. The effect on infiltration rates, as measured by Freon-12 tracer gas dilution, becomes marked if the central duct fan is operating. Duct fan on and duct fan off measurements of the rate of air exchange gave mean values of 0.41 and 0.78 ach respectively in a total of 31 homes.
Presents data on the air infiltration and ventilation rates in 2 large commercial buildings. One building is a 4 storey, 10000m2 office building near Glasgow, Scotland; the other is a 26 storey, 100,000m2 skyscraper in Newark NJ. Collects the data on air infiltration and ventilation rates by a micro-computer based automated air infiltration system which controls the injection of a tracer gas into the various zones of the building and monitors its decay.
Describes the general methodology for ventilation measurements by tracer gas, using decay, constant concentration and constant emission methods. Defines ventilation efficiency and the ways in which it can be experimentally determined. Gives the results of a series of lab measurements to determine the accuracy of the decay method under different conditions, and the efficiency of some mechanical ventilation systems.
Grab sampling of a tracer gas/air mixture in conjunction with the tracer gas decay technique is a convenient method for conducting a survey of air infiltration rates in homes. Examines such a method, using SF6 as the tracer gas and storing the concentration in evacuated glass tubes.
Using miniature perfluorocarbon tracer (PFT) sources and miniature passive samplers, tests conducted in the lab and in a typical home successfully demonstrate the utility of the PFT kit as a means for implementing wide-scale infiltration meas
Uses the SEGAS "Autovent" constant concentration apparatus to measure the fresh air entering and the local ventilation rate in each cell of amulti-celled dwelling with both natural and mechanical extract ventilation. Measures fresh air entry into each cell using tracer gas constant concentration and decay techniques. Conducts decay tests without artificial mixing, and interprets them by computing the area under the decay curve to obtain local ventilation rates. Compares the 2 measurements, giving the ventilation efficiency of each cell and an idea of air quality in each room of the house.
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