Photon and neutron dose evaluation in experimental hall of Indus-1 Synchrotron Radiation Source

Abstract

Radiation measurement in Indus-1 experimental hall and Control Room area was performed for evaluating the photon and neutron dose rates during various operating conditions. The measurements were carried out using VICTOREEN 451 P and LUDLUM Model 2363 survey meter for photon and neutron dose rate measurement, respectively. From the measurements, it was seen that during Indus-1 injection, maximum photon dose rate of 410 µSv/h and maximum neutron dose rate of 15.9 µSv/h have been observed at the hot spots (at pre-mirror locations of HRVUV Beam Line and Photo Physics Beam Line). At experimental station of the beam lines, the neutron dose rates observed were in the range 1.0-3.4 µSv/h whereas the photon dose rates were up to 0.9 µSv/h. During Indus-1 storage condition, the radiation levels were near background levels except at one of the hot spots (pre-mirror, Photo Physics Beam Line) where photon and neutron dose rates observed were 6.3 µSv/h and 45.1 µSv/h, respectively. During Indus-2 injection, neutron dose rates ranging from background to 3.3 µSv/h were observed in the sitting area at experimental station whereas photon dose rate was noticed up to 0.4 µSv/h. For the control room area, neutron dose rates up to a maximum of 3 µSv/h were observed during Indus-1 injection only. During other operation modes, dose rates in control room are of background level. In view of the data during injection mode of Indus-1, entry prohibition is re-confirmed to the experimental hall whereas it is restricted during the storage (user) mode. Details of the measurements and results are presented in the paper.