Raised radon gas levels are known to exist in mines and Show Caves, and in the United Kingdomthe Ionising Radiations Regulations 1985 require the employer to take action to reduce radonlevels by improving ventilation or restricting access, because significant radiation doses can bereceived by workers.In the Mendip Hills, where the underlying rock gives rise to raised radon levels in domesticdwellings, there are a number of cave systems with unrestricted access to recreational cavers;including youth groups.
Radon gas is now considered to be a health hazard when found in excessive amounts in the builtenvironment. The levels of radon vary greatly, with some geographical areas having very highlevels. In the United Kingdom, Northamptonshire was declared an Affected Area in 1992, and itwas at this stage that our group first started studying radon levels and the steps taken to reducethem.The radon levels both before and after remediation were studied, together with the number ofoccupants of affected rooms, and their pattern of occupation.
The indoor radon program in the US. started in the early 1970's in response to CongressionalHearings that recommended the initiation of radon measurements in certain parts of the united Stateswhere enhanced radon caused by contaminated uranium and radium tailings was suspect. In the mid1970's, the Department of Energy (DOE), Environmental Measurements Laboratory (EML),conducted the first indoor radon survey in the New York City Metropolitan area. The two year studyrecommended that radon surveys should be expanded throughout the US.
A newly built radon calibration test bench called BACCARA is presented. A method of calibrationusing a secondary 222Rn standard is described and examples of calibration are given. With thismethod, no reference instrument is needed and one obtains a more accurate determination of the222Rn volume activity.
Indoor 222Rn concentrations are influenced by several factores which may change with time,thereby causing temporal fluctuations of radon concentrations in rooms.
A national survey of indoor radon levels in Lithuania was performed between 1995 and 1998. The main objective of this survey was to evaluate the average of indoor radon concentrations in Lithuania and to determine whether there were significant variations with different areas.
This study describes an approach for measuring and modeling diffusive and advective transport of radon through building materials. Goal of these measurements and model calculations is to improve our understanding concerning the factors influencing the transport of radon through building materials. To reach this goal, a number of experiments has to be conducted. These experiments, including measurements in a large cylinder for creating diffusive and advective transport of radon under controlled, dwelling-like conditions, are described here and the initial results are presented.
Various methods to determine ²²²Rn concentration in soil gas were tested at two sites with different soil types in a depth of 1 m. They include instantaneous (spot), continuous (real time) and timeaveraging procedures with advective ('active' procedures)
There is a currently growing interest in the effect of exposure to 222Rn, because it became recognised as an important “pollutant” factor of the environment. Possible lung cancer incidence due to exposure to environmental radon levels may thus account for
If indoor radon levels are to be significantly reduced across Europe it is essential to ensure that allnew buildings built in areas affected by radon are protected against radon.In the United Kingdom the Building Research Establishment Ltd (BRE) have been carrying outresearch on behalf of the Department of the Environment, Transport and the Regions (DETR) todevelop protective measures for use in new buildings. This work commenced in the mid-1980sand has resulted in the development of a range of practical cost-effective techniques for providingradon protection in new UK buildings.