Commissioning Dosimetry and Dose Mapping of the Tunisian Gamma Irradiation Facility and Comparison with MCNP Monte Carlo Simulation

Cobalt-60 irradiation facility has been put into operation at the National Centre of Nuclear Sciences and Technology at Sidi-Thabet in Tunisia. Technical specifications were checked by dosimetry commissioning experiments and compared to Monte Carlo simulation data using MCNP. Installation qualification has been carried out to measure absorbed dose distribution in the irradiation cell and products. Two dosimeter systems were employed for measurements: Red and Amber Perspex and Cellulose Triacetate (CTA). The regions of minimum and maximum absorbed dose within a homogeneous dummy products and the dose uniformity ratio were determined. The products were loaded in carrier by sawdust with a bulk density of 0.114 g/cm3, potato with a bulk density 0.58 g/cm3 and syringe with a bulk density 0.123 g/cm3. The isodose curves and the three dimensional views were built using the kriging method. An acceptable agreement in most sets between Monte Carlo simulation results and the experimental values.