Radiation safety workers in Fukushima, Japan have helped a doctoral student at Lund University in Sweden demonstrate that ordinary table salt can be used to measure radiation exposures.
The radiation safety workers carried small packets of salt in light-tight containers while they worked as well as traditional dosimeters.
By taking advantage of optically stimulated luminescence (OSL), scientists can use the light produced by a special blue LED to determine the radiation dose.
When analyzed, the measurements taken from the salt dosimeters corresponded with measurements gathered from the traditional dosimeters.
The findings may help health physics experts validate models and help estimate public exposures after significant radiation releases.
Despite the fact that scientists have thought of using salt as a dosimeter or radiation detector since the Chernobyl disaster in 1986; today, generally only personnel in rescue teams responding to a radiation release or nuclear emergency carry dosimeters.
While this is useful in monitoring the dose received by emergency personnel, it does little good in helping estimate the dose received by the public, or determining the amount of shielding that may have been provided by different structures.
The research conducted by Maria Christiansson at Lund University showed that a linear dose response could be found in the interval 1-100 mGy and that the salt dosimeter would provide detection limits down to about 0.2 mGy.
Christiansson showed that salt in packages which kept light out could be relied upon to store the OSL signal for several months.
Source: Lund University