In the present work performance of film badge as an alternative personal dosimeter for thermal neutrons is investigated. To do this, a cadmium-lead (Cd-Pb) filter with the same thickness as the tin-lead (Sn-Pb) filter is attached to the AERE/RPS badge. Since thermal neutrons are mixed with gamma rays, the dosimeter is irradiated by the 60Co gamma rays standard field of Karaj Secondary Standard Dosimetry Lab as well as the mixed neutron-gamma field of the radiography beamline of Isfahan Miniature Neutron Source Reactor. In the both fields, ten personal dose-equivalent values between 0.1 to 10 mSv are chosen. For any dose, three film badges are used and the net optical density is determined as the average of their optical densities. Finally, the calibration curves of the film badge are plotted to determine the dose-equivalent values. Obtained results reveal that film badge simultaneously determines the thermal neutrons and gamma rays dose fractions. Also, the thermal neutron doses are at most 50% different from the nominal values considered.
- Film badge has is experimentally investigated as an alternative dosimeter for thermal neutrons.
- A Cd-Pb filter with the same sensitivity of Sn-Pb filter is used to determine neutron dose.
- With Cd-Pb filter in the badge, the dose fractions of neutrons and gamma rays can be measured.
- Between 0.1 and 10 mSv, the neutron dose-equivalent differs 50% from the nominal values.