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Sources of radon and the high levels of radon in many locations and building materials in Sweden are considered. Improvements in energy conservation through the reduction of ventilation rate have lead to very high levels of radon over 1000 BqRnD/m3 in some houses. Recommendations on acceptable levels of gamma radiation on building sites and radon concentration in dwellings are given. It is estimated that there are 30-40,000 dwellings over the Swedish recommended limit of 400 BqRnD/m3 requiring modification.

Air leaks which can bypass attic insulation in US wood framed houses are identified. Examples of heat loss paths include gaps at the entry of plumbing, heating or cooling ducts and electrics gaps around flues, and trapdoors. Remedial measures discussed include stuffing gaps with fibreglass, weatherstripping, taping polythene sheet over gaps, sealing and insulating ducts, and covering ceiling fan vents during the winter.

Individual mathematical models for formaldehyde concentrations in each of 3 normal rooms in a single family house is used to estimate ventilation rates needed to maintain formaldehyde concentration below the recommended Danish indoor standard (0.15 mg/m3). In an initial period after the house was finished a ventilation rate more than 10x the recommended Scandinavian maximum value (0.5 ach) was needed to keep the concentration below the indoor standard.

There have been considerable efforts to estimate risks to health from the present level of indoor air quality. However, there has been comparatively little work to relate these calculated risks to other risks of energy use or conservation, or to determine how large these risks will be in the future. This paper finds that, on the basis of extrapolated trends, risk associated with changes in indoor air quality in the United States. The other two are associated with the expected change to smaller automobiles and the entire coal fuel cycle, from producing electricity to synthetic fuels.

States that the higher internal humidity and lower structural temperatures in UK timber frame houses, as compared to the US and central Europe increases the risk of interstitial condensation. Condensation risk has also increased in all countries because of energy conservation measures and changes in heating patterns, occupation density and moisture production. Gives recommendations for the prevention of interstitial condensation.

Describes research work in Finland concerning air infiltration and ventilation in buildings from 1979. Types of ventilation system in finnish houses, flats and other buildings are discussed. Reports on a model developed to predict the correlation between various factors and air infiltration. Gives a summary of pressure test measurements carried out in a few hundred small houses, and presents proposals for recommended airtightness levels in new buildings. Describes warm air heating systems, heat recovery systems in flats, and maintenance problems with ventilation systems.

Presents results obtained in field studies of control and test houses provided with low cost retrofit infiltration controls. There are significant estimates of average energy savings during both heating and cooling seasons. However, the 95% confidence intervals for the heating season span the origin and theprobability that savings were actually observed is less than 85% for the heating season. The probability that actual savings were measured during the cooling season is >95%.

Describes trials undertaken by BRE and ECRC at Inverclyde to test small domestic electric dehumidifiers in council houses. Assesses 3 types of machine, selected to give a range of extraction rates from 1-4 kg per day. These were supplied free of charge and the running costs reimbursed. Shows that the equipment did lower the moisture levels in the houses satisfactorily. Preliminary analysis of results show that the early BRE model predicting moisture and ventilation interactions work well.

Describes a 2 year study sponsored by EPRI to ivestigate relationships between energy use, air infiltration and indoor air quality. Uses 2 bi-level, detached houses, identical in design and wind exposure. Continuously monitors parameters related to related to energy use, air infiltration, and indoor air quality.

Examines the sensitivity of the predicted air infiltration rate to measured building air tightness data and the wind exposure index determined from site inspection. Presents results of air tightness tests in New Zealand houses, which indicate the range of leakage resistance for components, for solid materials (such as wall and ceiling lining materials) and for cracks separating major components such as floors and walls.