Comparison of LiF:Mg,Cu,P (MCP-N, GR-200A) and α-Al2O3:C TL detectors in short-term measurements of natural radiation

Results are reported of tests of GR-200A (LiF:Mg,Cu,P Chinese production), MCP-N (LiF:Mg,Cu,P Polish production) and α-Al2O3 highly sensitive TL detectors used in short-term measurements of natural radiation performed within the EU Intercalibration by the Polish (INP) and Spanish (CIEMAT) participants. The experiment was carried out in Roskilde, Denmark, by Riso National Laboratory. To assess only the cosmic component of natural radiation, detectors were exposed on a wooden pier. The actual dose rate was monitored over the total exposure time of three days by a Reuter-Stokes high pressure ionisation chamber. Results obtained with MCP-N and GR-200A were, for both teams, about 32 nGy.h-1, for α-Al2O3:C about 49 nGy.h-1, while the chamber-evaluated mean dose rate was about 40 nGy.h-1. It was found that all tested detectors (MCP-N, GR-200A and α-Al2O3:C) are capable of measuring natural gamma dose rates after an exposure of only a few hours. (Author)