Natural ventilation rates in bedrooms at night have been measured in retrofitted apartments. The measurements indicate clearly that air quality in bedrooms may be unacceptable in dwellings with an energy-efficient minimal ventilation rate. The air supply rates may be as low as 1 l/s/person in themedian case of bedroom size, ventilation rate and two occupants. The carbon dioxide concentration will reach a level of 4000-4500 ppm in the morning depending on the length of sleeping time in a closed room.
Reviews the most important sources of indoor air pollutants, and means of measuring the contamination of room air by persons (carbon dioxide and odours). Lists some recommendations for minimum ventilation rates, based on the results of experimental investigations.
From a hygienic viewpoint, optimum indoor air quality can be characterized as the complete absence of pollutants. The most important sources of such pollutants are reviewed, including those entering a room from outside, those generated by human activity and those emanating from various materials. Thebasic requirement is for all emissions to be as low as possible. For CO2 and formaldehyde the existing standards are reasonable. For most of the other substances it is not recommended to define tolerable limit values since such definition may decrease the efforts to attain a zero level.
Reviews literature on indoor air quality in housing, nature of contaminants and their sources, health effects, standards and guidelines, impact of air sealing on indoor air quality, sources of uncontrolled air leakage, airtightness and natural ventilation, airtightness of new and existing housing stock, air change in new and existing housing, impact of air sealing on airtightness and ventilation, indoor air quality in tight houses, impact of occupant behaviour on ventilation, measures to improve indoor air quality, identifying problem houses, indoor pollution control strategies, and ventila
A study was conducted in 40 homes in the areas of Oak Ridge and West Knoxville, in the summer and winter months, to quantify concentrations of COx, NOx, particulates, formaldehyde, and radon, as well as selected volatile organic compounds.
Under the provisions of the Law for Maintenance of Sanitation in Buildings, the "Building Sanitation Control Standards" came into force subsequently. The air quality standard, one of these Standards, is composed of the following 6 items: Suspended particles, carbon dioxide, carbon monoxide, temperature, relative humidity, and air velocity. Since the enactment of the law, we have surveyed actual conditions of indoor environment for these 13 years, and found the percentage of buildings which failed to come up to the standards.
Reviews current knowledge about the sources of a number of indoor pollutants and their concentrations: tobacco smoke, NO2, CO, radon, formaldehyde, SO2, CO2, O3, asbestos, mineral fibres, organics and allergens. Lists the adverse health effects from exposure to each of the pollutants. Finds instrumentation for measuring exposure acceptable, but monitoring and knowledge of distribution of sources and concentrations inadequate or marginal. Knowledge of exposure-effects relationship is inadequate, especially with regard to delayed effects of chronic exposures.
Long-term monitoring of radon, aerosol and carbon dioxide concentrations was carried out in two Finnish public buildings. In each case, a distinct periodic behaviour of pollutant concentrations was observed. CO2 and aerosol showed maxima during the working hours, but the fluctuations of the aerosol concentration were faster and more irregular. The radon concentration peaked at night and on weekends, dropping off rapidly in the working day mornings when ventilation was turned on.
40 female and 39 male judges have each evaluated the intensity and acceptance of body odour 29 times on entering an experimental auditorium occupied by 105 women. During the experiment, which lasted three hours and 50 minutes, the ventilation rate was varied while the air temperature was kept constant around 20-21 deg C. Carbon dioxide was measured continuously. No substantial difference was found in the ventilation rates required in spaces occupied by women and men. A ventilation rate around 8 l/s per person is required to satisfy 80% of people entering a space.
When indoor air concentrations from indoor combustion processes are estimated, source strengths and ventilation rates are usually considered. Recent studies, conducted in the Energy Research House at Iowa State University, indicate that seve
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