Application of the advanced radon diagnosis methods in the indoor building environment.

The health risk and dose calculations from exposure to indoor radon and its decay products are generally based on long-term integral measurements and standard ICRP recommendations. In this context, the results of assessments predicate more about human activities inside the building instead of a quality and an effectiveness of applied measures against the radon. The present paper is focused on a set of different measuring techniques and methods practically used for a classification of buildings regarding to the radon protection requirements. The fundamental quantitative and qualitative procedures of radon transport pathways and radon sources analysis, commonly named as radon diagnostic methods are performed in detail.

Radon diagnosis procedures focused on dwellings with ineffective measures against radon.

An efficiency analysis of remedial measures launching in the Czech Republic before 2004 revealed that in 52% of houses the remediation was not successful. An example of the house with an ineffective mitigation is described in order to present radon diagnosis procedures focused on the identification of critical factors responsible for the remedial mitigations insufficiency. A description of additional measures application is presented and results of the final efficiency evaluation are discussed.

Investigation and remediation of houses affected by radon phenomena connected with earlier exploration of silver and uranium ore.

The sources of gamma radiation inside buildings affected by earlier silver and uranium mining activities are discussed. Possibilities how to reduce gamma dose rates from building materials were studied on several houses located in the old mining town Jáchymov. Results of the efficiency analysis are presented. Experience obtained up to now indicates that it is almost impossible to reduce the gamma dose rates in such buildings to the level corresponding with the natural background, because some of the gamma radiation sources cannot be completely removed from the building structures.