Experience of Application of New Remote Controlled Instruments for Scanning of Distribution of Radioactive Contamination in Rooms With High Dose Rate

Abstract

When carrying out the decommissioning of nuclear facilities is necessary to measure the distribution of radioactive contamination in the rooms and the equipment at high levels of background radiation. In the decommissioning of the reactor in the MR NRC “Kurchatov Institute” for such problems is developed and applied a few special systems with remote control. For a survey of high-level objects used mounted on the robot radiometric system. To determine the composition of pollutants and use a portable collimated spectrometric system. To obtain a detailed distribution of contamination of used remote-controlled gamma camera.

Measurement of low-activity uranium contamination by gamma-ray spectrometry for nuclear decommissioning

“…When dealing with deep contaminations in concrete, the scattering of gamma rays can hinder the precise localisation of the contamination. Methods using collimators can be employed to counter this effect [12], allowing a better mapping of the contamination [13].…”

“…We introduce an absolute and unilateral test, able to differentiate the acquisition times between the reference period (ƒ ‡!ˆ) and the test period (ƒ :!2: ). This test is simple in the sense that it only requires a total counting in both the regions of interest of 235 U and the region of interest of 238 U: B = A140 J 148C š A160 J 166C š A182 J 188C š A202 J 208C š A998 J 1004C keV (13) The cumulative function is built under the H0 hypothesis of an identical counting intensity between the two acquisitions. Let G ‡!ˆA BC be the associated counting of the reference background signal and ›ABC the associated counting rate.…”