Radon Levels in Romanian Caves: An Occupational Exposure Survey

A comprehensive radon survey has been carried out in seven caves located in the western half of Romania’s most significant karst regions. Touristic and non-touristic caves were investigated with the aim to provide a reliable distribution of their radon levels and evaluate the occupational exposure and associated effective doses. Radon gas concentrations were measured with long-term diffusion-type detectors during two consecutive seasons (warm and cold). All investigated caves exceed the European Union reference level of radon gas at workplaces (300 Bq/m3). The radon concentration in these caves ranges between 53 and 2866 Bq/m3, reflecting particular cave topography, season-related cave ventilation, and complex tectonic and geological settings surrounding each location. Relatively homogeneous high radon levels occur in all investigated touristic caves and in Tăuşoare and Vântului along their main galleries. Except for Muierii, in all the other caves radon levels are higher during the warm season, compared to the cold one. This suggests that natural cave ventilation largely controls the underground accumulation of radon. The results reported here reveal that the occupational exposure in Urşilor, Vadu Crişului, Tăuşoare, Vântului, and Muierii caves needs to be carefully monitored. The effective doses to workers vary between an average of 0.25 and 4.39 mSv/year depending on the measuring season. The highest values were recorded in show caves, ranging from 1.15 to 6.15 mSv/year, well above the European recommended limit, thus posing a potential health hazard upon cave guides, cavers, and scientists

The effects of the 2007 global economic crisis on firm relocation factors: SME movements from Greece to Bulgaria

This chapter examines the ways in which the 2007 global economic crisis has influenced firm relocation factors. Firm mobility constitutes a dynamic process, with its aspects changing in response to significant broader processes, such as globalisation. Specifically, the recent crisis has modified the socio-economic conditions under which firms operate. In order to examine the crisis-driven changes in firm mobility, this chapter employs a comparative analysis of the pre- and post-crisis relocation of Greek small and medium-sized companies to Bulgaria, which has recently increased. Greece is at the epicentre of academic and political debate in Europe, being the European Union member state mostly affected by the crisis. In the context of the changing economic and institutional conditions, it is demonstrated that the significance of the firm relocation factors, such as labour cost and level of demand, records considerable differences between the pre- and the post-crisis period