Tracing of radon leakages

In Sweden there are two major sources to indoor radon, the building material and radon from uranium rich soils. It is now widely accepted that indoor radon daughter concentration in Sweden, higher than 1000 Bq/m3 is most frequently caused by

Assessment of additional exposures and risks from airtightening of homes in an Alpine area with high radon emanation

In large areas of the Swiss Alps, the high radium content of rocks and soil, which results in high source terms for radon from the ground, may produce considerable indoor levels of radon in dwellings with low air infiltration. During the winter

Survey of radon concentrations in Dutch dwellings

Radon concentrations were measured in about 1000 Dutch dwellings and at 200 outside locations using passive monitors. A median concentration of 24 Bq/m3 was found for the dwellings with a highest value of 190 Bq/m3. Seasonal effects were found to be small. Correlations were observed between median radon concentrations and construction parameters including ventilation rate. The concentrations outside show an unexpected dependence on the location. Comparison with previous grab-sampling data on radon-daughter concentrations reveals an average equilibrium factor of 0.3.

Exposure of the Swedish population to radon daughters

Three different investigations of radon in Swedish dwellings are presented - a nationwide study conducted primarily to determine the collective dose to the Swedish population from exposure to radon and radon daughter, a supplementary study of newly built detached houses in order to find out whether theregulations in the Building Code prescribes acceptable radon levels in new houses built on normal ground, and measurements made by the local authorities in order to find houses with levels of radon daughters above the norm.

Transport of radon from soil into residences

To develop effective monitoring and control programs for indoor radon it is important to understand the causes of the broad range of concentrations that have been observed. Measurements of indoor radon concentration and air-exchange rate in dwellings in several countries indicate that this variability arises largely from differences among structures in the rate of radon entry.

The effect of tracer gas on the accuracy of air change measurements in buildings

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.

Urea-formaldehyde foam cavity wall insulation. Reducing formaldehyde vapour in dwellings

Methods discussed include ventilation, excess foam removal and sealing accessible gaps.

Volatile organic levels in indoor air

Volatile organic chemicals in indoor air of a home-for-the-elderly and a new local government office building were identified and quantified using Texax GCR samplers and capillary gas chromatography/mass spectrometry analysis. Over three hundred chemicals were tentatively identified in indoor air of thehome-for-the-elderly. Comparison of night-day levels were made. The new office building was also part of a longitudinal study which revealed a rapid decrease in levels with time for some chemicals (after completion) while others increased.

Research-designed low-energy house

Treats a research study by the Danish Building Research Institute to develop a comprehensive set of design details for the use of bricks in a highly insulated cavity wall and building methods that could easily be followed by contractors. Illustrates photographically and describes the detached house which resulted from the project. Illustrates structural details diagrammatically. The energy consumption of the house is less than a quarter of older houses of similar size. Explains the design details to avoid thermalbridges and the application of modular coordination.

Air intrusion effects on the performance of permeable insulation systems

The R-values of permeable insulation systems are generally determined in test apparatus designed to assure one-dimensional heat transfer and to assure no air intrusion effects. Such classical R-values are used to help describe insitu heat-tra

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