Thermoluminescence characteristics of NaCl from Different Origins

Abstract

In radiological emergencies, table salt can be considered an established method for the retrospective dosimetry of past exposures and the dosimetry of potentially exposed people, where it is a material that can be expected to be easily available in accident locations and it can easily be sampled collection. The characteristics of thermoluminescence (TL) have been studied for four different commercial salt samples (NaCl) obtained from different sources. Indian salt (supplied by oxford lab) is used for comparison, not for measuring doses, Egyptian table salt (SAL), Saudi Arabian table salt (MASA) and British table salt (Cook's), are the three nominated types of salt to procedure in this work. Samples were irradiated with Gamma source using Cs-137. TL analysis of the samples were done using Harshaw Model 4500 TLD Reader, with WinREMS (Windows Radiation Evaluation and Management System) at heating rate 5 o C /sec with final temperature set to 350 o C. One prominent glow peak is observed in the glow curve at around 216-222 o C of the commercial salt samples. For all salt samples, the TL intensity of the glow curve is direct proportional to the grain size. By comparison the highest TL intensity for each salt sample, it is found that, Cook's salt is the most sensitive and preferable one to complete the study. The results show also that, TL intensity of the chosen salt (Cook's salt) has a linear response with the dose for a broad range from 250 mGy to 20 Gy. The post-irradiated fading rates are investigated and show stability after 8 days. The fading at room temperature was monitoring during 24 days. Cook's salt may be candidate for using as a Gamma ray retrospective dosimeter.

Dosimetric properties of thermoluminescent NaCl pellets from Khewra Salt Mines, Pakistan

“…The peak P3 lies within the general dosimetric peak temperature range (180–250°C). [ 42 ] Another high temperature peak (P4) appears between 250 and 260°C at high dose (10,000 mGy). The glow curve's dominant peaks indicate that irradiation caused the formation of multiple luminescent centres.…”

“…The peak P3 lies within the general dosimetric peak temperature range (180-250 C). [42] Another high temperature peak (P4) appears between [18,22,43,44] However, the small variations between peak heights amongst the observed and reported cases could be attributed to the diverse sites, origin of the analysed samples, impacting the nature and concentration of impurities. It must be noted that these impurities have a significant impact on the TL characteristics.…”