Test of household salt read by optically stimulated luminescence (OSL) as a personal dosemeter

摘要

This study has investigated the optically stimulated luminescence (OSL) of household salt andchemically pure NaCl after exposure in different radiation environments. The response relative tothermoluminescent dosimetry using LiF has been investigated to determine if OSL in NaCl can be considered asan alternative to measurements of thermoluminescence in LiF. A selection of staff members at the DiagnosticCentre and the Department of Radiation Physics at Malm? University Hospital (UMAS) carried small light-tighttubes, 3 mm (?) × 27 mm filled with salt. The measurements were accompanied by LiF-TL dosemeters using theregular system for personal dosimetry at UMAS. Similar kits of salt dosemeters were also positioned on the insidewalls of a nuclear medicine laboratory and a proton therapy room at the The Svedberg Laboratory in Uppsala.NaCl-OSL dosemeters were also placed in the primary radiation beam of a mammography unit. The OSL in thesalt was measured using an OSL reader (Ris? TL/OSL DA 15) at a temperature of 100°C using continuous waveOSL (CW-OSL) with blue LEDs (λ=470 nm). The TL-measurements were made with a TLD reader (RadosDosacus) using 4.5 mm (?) × 0.9 mm LiF: Mg, Ti (Harshaw). Preliminary results show that household salt can beused to measure absorbed doses down to 200 μGy. Measurements also indicate a somewhat higher responserelative to LiF-TL dosemeters at low photon energies. The effect may be attributed to the higher atomic number ofNaCl (Z=11, 17) compared with LiF (Z=3; 9). We conclude that NaCl-OSL dosemeters appear to be an interestingalternative to TL dosemeters at occupational exposure.