7. SURVEY PLAN FOR HONG KONG POLYTECHNIC
Currently the situation in Hong Kong is characterised as such :
a) routine monitoring of environmental gamma dose rate is carried out at 10 selected fixed stations in the Hong Kong area by the Royal Observatory. Also, this institution has the capability to conduct field studies with the use of a van. In addition, this institution has the infrastructure for fallout monitoring in the field.
b) EPD, jointly with the University of Hong Kong, is in the process of conducting a large scale radon survey in the Hong Kong area;
c) the City Polytechnic is engaged in radon exhalation measurements.
In view of the above ongoing activities and to aim for the optimum use of the limited resources at the Hong Kong Polytechnic it is necessary to focus on a specialised, basic research oriented activity rather than on the duplication of large scale surveys conducted already. Therefore a plan was designed which addresses the most topical subjects, but takes into account the above constraints.
The most important topics at this stage in Hong Kong are to determine whether there is any contribution of radon from the subsoil underneath the dwellings to the indoor radon level and the thoron contribution in general. All future technical and regulatory actions will depend on the assessment of these components. Therefore such a survey should encompass the following aspects:
a) selection of a set of buildings, representing the major architectural styles found in Hong Kong for homes;
b) as above but for offices and public buildings;
c) long-term integrating radon measurements in different parts of these buildings, particularly at sites such as lower parts of buildings, lift shafts, staircases, ventilation ducts acting as potential inroutes for radon gas into the building;
d) as in c) but for thoron gas
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