Dose Measurement of Hard X-ray Produced by Damavand Tokamak by Means of LiF:Mg, Cu, P TLDs

Damavand tokamak is the source of soft and hard X-ray by hydrogen working gas in plasma duration time. As such devices are widely used in fusion researches, it is required to comply with radiation protection standards and monitor radiation dose output. In this paper the dose measurement of hard X-rays produced by Damavand tokamak has been done in order to perform the necessary protection arrangement in torus area. All experiments were done by Thermoluminescence crystal dosimeter tools of the type LiF:Mg, Cu, P crystals. The results showed that radiation levels around the torus are very high (in the order of several mSv per shot) and various dose levels in different points (in terms of distance and height of device) imply the anisotropic spatial distribution of measured dose. According to the measurements during 100 shots of Damavand tokamak, the total dose in the shielding room which is 5 m away from torus, is above the permissible level. In order to control personnel safety, it was designed and constructed a lead shielding wall with 5 cm thick and 2 m x 7.5 m dimensions and the performed dosimetry operation after installation of wall shows a mean value of 96.33 % reduction in measured dose due to presence of lead shielding. Thus there will be possibility of doing 25,000 shots/year in safe condition.