Notes the large savings possible if ventilation were adapted to the prevailing need. A promising possibility for indicating occupancy and thus the ventilation requirement is measuring the level of carbon dioxide. The project includes a test with equipment for CO2-monitoring of the exhaust air flow in an office building which controls the volume of outdoor air supply, thusmaintaining the CO2 level constant. Measures how the CO2 level can vary locally,how other pollutants in air can vary, how much energy can be saved.
Studies the airtightness of about 50 passive solar homes located through out the USA using low cost measurement techniques. Measures include pressurization tests to measure airtightness and tracer gas measurements to determine air infiltration rates. Pressure tests show a variation in airtightness of homes from 3-30 changes/hr at 50 Pa, with a median of 5-9 changes/hr.The air infiltration measurements cover a wide range from 0.05-3 changes/hr, with a median of 0.5 changes/hr. Finds that these passive solar homes are not significantly tighter than less energy-conscious houses.
Investigates the efficiency of models describing infiltration and natural ventilation in buildings. Considers 8 different models. The parameters of the models are determined by fit to data from 6 different ventilation experiments in residential buildings. The number of parameters in each model is varied and the effect of this on the model efficiency is evaluated. The effect of simple corrections of the models for a dependence on the wind direction is considered.
Describes a field study carried out to evaluate the effectiveness of the air leakage sealing techniques employed by Ener-Corp Management Ltd. for reducing air infiltration in houses. Performs presealing and postsealing air leakage tests on 82 single detached houses, located in Winnipeg or southern Manitoba. The sample group consisted of 56 conventionally-constructed houses of varying size, style, occupancy and airtightness, and 26 nonstandard structures of smaller but identical size and age. This latter group was part of the Flora Place Project.
Tests a method which determines the infiltration of air and radon from the soil to a building. Makes measurements of total air flow along with usual airtightness tests. Describes practical tests in a detached house with a raft foundation on a gravel esker, and determines the permeability curves for thewhole house and the raft alone, and also the permeability of the soil to air. Describes the way the results are used for determination of air infiltration in different climatic conditions, and tests different radon reducing methodsusing the previously developed system analysis.
Discusses the extension of an infiltration predicting technique to the prediction of inter-room air movements. Air flow through openings is computed from the ASHRAE crack method together with a mass balance in each room. Verifies technique by comparison to published experimental results. Results indicate that the simple model provides reasonable results for complex 2 way flows through openings. The model is as accurate as the available data, about+-20%.
Studies the techniques and issues related to evaluating the airtightness of homes. The first section discusses the physics of air infiltration and the techniques used to measure infiltration rates. Also discusses pressurization testing and its relation to infiltration. The second section presents experimental work aimed at several questions raised in the first section. A long term experiment involving weekly pressurization testing of a home reveal the short-term reproducibility of the test results and the seasonal variation in a home's tightness.
States that in a tight house with a vapour barrier, an air management system is needed to provide fresh air and remove the build-up of moisture generated by the occupants. Briefly describes a typical air management system,incorporating an air-to-air heat exchanger, and discusses the need to provide an acceptable ventilation rate, which controls pollutant level but minimizes heat losses.
Describes some new theoretical and experimental techniques developed by British Gas to investigate the ventilation of buildings. These include:< 1. The multi-cell model "vent" for predicting ventilation rates< 2. "Autovent", the multi-cell constant concentration tracer gas technique used for measuring ventilation patterns in buildings.< 3. Pressurization techniques for measuring air leakage in buildings.< Gives a selection of results from applications of these techniques to show their scope.
Studies the ventilation of 9 air-conditioned animal rooms used for both housing and experiments. Samples dust, measures ventilation rate by anemometers and by tracer gas decay, and uses settle plates to determine the number of airborne bacteria. Detects a high amount of pariculate matter emanating from the animals which might sensitize personnel working in these rooms. Previously, attention has been paid to the ventilation requirements of the animals but where people also spend several hours in animal rooms then safety conditions for staff must be considered.
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