Radiation Protection Dosimetry 66:135-138 (1996)
© 1996 Oxford University Press
Long-Term Investigation on Self-Irradiation and Sensitivity to Cosmic Rays of TL Detector Types TLD-200, TLD-700, MCP-N and New Phosphate Glass Dosemeter
The cosmic component of background gamma radiation, the intrinsic background (or 'self-dose') and fading of TLD-600, TLD-700 and TLD-200 (all produced by Harshaw), MCP-N (LiF:Mg,Cu,P) produced by INP Kraków) and phosphate glass dosemeters SC-1 (Toshiba Glass) were measured over a period of 557 days at the Asse salt-mine 775 m below ground level, in a steel shielding at the TZK (Karlsruhe Research Centre) laboratory and in a buoy off-shore of an artificial lake. Assuming a reference cosmic dose rate of 37 nGy.h-1 over the lake, the relative response to cosmic rays was estimated at 0.76 for the LiF:Mg,Ti and CaF2:Dy detectors and 0.86 and 0.81 for the phosphate glass and LiF:Mg,Cu,P detectors, respectively. Fading of detectors of all types did not exceed 5% per annum, including long-term storage at 33 oC in the salt mine.