Effective dose assessment for workers in caves in the Czech Republic: experiments with passive radon detectors

Abstract

The new RAMARN system for radon volume activity measurement was developed in 2003 and has been in use since then. RAMARN system consists of a plastic chamber that is conically cylindrical in shape and about 0.5 l in volume; a bare Kodak LR 115 is located on the bottom of this diffusion chamber. The size was chosen to avoid the influence of deposited decay products of radon. Kodak has a spectrometric character--the tracks are visualized only for alphas with energies between 1 and 3 MeV that touch the foil; thus the effective volume has a lens shape. The response therefore corresponds to diffused radon and half of (218)Po born by radon gas decay. The experiments described below were conducted as one part of a routine methodology control, focused on classifying worker irradiation from natural ionizing radiation sources in show caves and in caves used for speleotherapy.

Nano Particles Including Radon Decay Products in Ambient Air

“…In addition to elevated radon levels, as found in many caves worldwide (Hakl et al, 1997;Cigna, 2005;Field, 2007;Vaupotič, 2010;Kávási et al, 2010), f un values are also high (Vaupotič, 2008b), as also in some other caves (Cheng et al, 1997;Sainz et al, 2007;Thinová & Burian, 2008). They are considerably higher than in Slovenian kindergartens (Vaupotič, 2007), schools (Vaupotič & Kobal, 2006) and wineries (Vaupotič, 2008a).…”

“…Thus, f un is very low in mines with high aerosol concentrations (Butterweck et al, 1992) and high in karst caves with very clean air (Butterweck et al, 1992;Cheng et al, 1997;Sainz et al, 2007;Thinová & Burian, 2008). Elevated f un values have been also observed in the Postojna Cave (Butterweck et al, 1992;Vaupotič, 2008b).…”

Indoor radon monitoring in selected fault zones, Slovakia – preliminary results from the summer monitoring period

“…Building characteristics as building material, window tightness, cellar, year of construction and reconstruction, number of inhabitants, intensity of ventilation and time spent in monitored rooms were obtained through a questionnaire, distributed to voluntary participants of the survey together with information leaflet about radon (Műllerová et al, 2016). Passive alpha track detector RamaRn (SÚJCHBO, Milín, Czech Republic), with Kodak LR 115 film located at the bottom of the diffusion chamber was used in this survey (Thinová and Burian, 2008).…”

Preliminary results of radon survey in thermal spas in V4 countries

“…The size was chosen to avoid the infl uence of deposited decay products from radon. The tracks are visualized on LR-115 fi lm only for alphas with energies between 1 and 3 MeV that touch the foil; thus the effective volume has a lens shape [10].…”