The activity of radon daughters in high-rise buildings.
Abstract Forty measurements are reported in similar rooms in two high-rise buildings. The geometrical means for the concentration of radon daughters including and excluding the basement results, respectively, were 0.90 and 1.00 mWL, which is less than the quoted mean 2.0 mWL for 65 measurements in typical houses in the same city. The frequency distribution of these measurements shows a log-normal distribution. The concentrations did not depend on the distance from ground level but may depend on the ventilation rate of the room examined. The correlation between the concentration of radon daughters in WL in rooms above the first floor in the two high-rise buildings with the inverse of their ventilation rate were 0.73 and 0.67, respectively.
Building Epidemiology and Investigations — Approaches and Results (U.S. Experience)
Most epidemiology studies and investigations of Sick Building Syndrome in the United States are conducted in complaint buildings in contrast to Europe where researchers have conducted several important studies in “non-complaint” buildings. Many investigations have been conducted by indoor air experts in relation to litigation, though few of these have been published in the open literature. There is a sizeable body of literature on U.S. investigations of “problem buildings” including two major recent studies of federal government facilities in Washington, D.C. Additionally, the National Institute for Occupational Health and Safety (NIOSH) has published individual reports and several summaries of more than 500 investigations it has conducted into complaint buildings. A lack of standardized protocols, measurement methods, and standards or guidelines for interpretation of results impedes comparison of study results and more rapid improvement in understanding the causes of “problem buildings” and effective action to prevent the problems from occurring. The federal government is now embarking on a program to address these lacks, although funding is rather small to meet the need.
Experimental study of water fluxes in a residential area: 2. Road infiltration, runoff and evaporation
Lack of accurate data has led some hydrologists and city planners to assume that urban infiltration is zero and runoff is 100% of the rainfall. These assumptions lead to an over estimation of road runoff volume and an underestimation of direct recharge to groundwater, which is already rising under some UK cities. This study investigates infiltration and runoff processes and quantifies the percentage of rainfall that contributes to storm drainage, and that which infiltrates through different types of road surface. Access tubes were installed for measuring soil water content using a neutron probe in three car parks, a road and a grass site at the Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford. Storm drainage was recorded at the exit of the Thamesmead Estate in Crowmarsh Gifford, just before the drain joins the River Thames at Wallingford. Rainfall and water table depth were also recorded. Weekly measurements of soil moisture content indicated that the top 40 cm layer is not influenced by water‐table fluctuations and, therefore, positive changes in soil moisture could be attributed to infiltration of rainfall through the surface. Depending on the nature of the surface, subsurface layers, level of traffic, etc., between 6 and 9% of rainfall was found to infiltrate through the road surfaces studied. The storm drainage generated by road runoff revealed a flow pattern similar to that of the receiving watercourse (River Thames) and increased with the increase of infiltration and soil water content below the road surface. The ratio of runoff to rainfall was 0·7, 0·9 and 0·5 for annual, winter (October–March) and summer (April–September) respectively. As the results of the infiltration indicated that 6 to 9% of annual rainfall infiltrates through the road surface, this means that evaporation represents, 21–24% of annual rainfall, with more evaporation taking place during summer than winter. Copyright © 2003 John Wiley & Sons, Ltd.