Title :
Surface activity and dose rate distribution inside 4th reactor hall of Chernobyl NPP
Author :
Chesnokov, A.V. ; Fedin, V.I. ; Gulyaev, A.A. ; Potapov, V.N. ; Smirnov, S.V. ; Shcherbak, S.B. ; Urutskoev, L.I. ; Volkovich, A.G.
Author_Institution :
Recom Ltd, Moscow, Russia
fDate :
6/1/1998 12:00:00 AM
Abstract :
A gamma locator designed to conduct contamination surveys inside the reactor hall of the Chernobyl NNP 4th unit is developed. The device consists of detector head and remote control computer connected with a cable (>150 m). The detector head is a collimated scintillator-based gamma-ray detector. It is installed on a scanning unit and is placed inside the reactor hall. The gamma locator scans all hall surfaces with a certain angle step and measures quantum flux from these directions. These data are used to determine the effective surface activity of contaminated surfaces. A distance between the detector head and surveyed surface is measured by a laser distance device. There is a small CCD camera inside the collimator. It obtains a visible image of the measured surface. An exposed dose rate distribution within the investigated volume is reconstructed by using the measured 137Cs effective surface activity
Keywords :
CCD image sensors; dosimetry; gamma-ray detection; nuclear power stations; radiation monitoring; radiation protection; solid scintillation detectors; 4th reactor hall; 137Cs effective surface activity; CCD camera; Chernobyl NPP; Cs; collimated scintillator-based gamma-ray detector; contamination surveys; detector head; dose rate distribution; exposed dose rate distribution; gamma locator; remote control computer; Collimators; Gamma ray detection; Gamma ray detectors; Goniometers; Head; Inductors; Pollution measurement; Power cables; Surface contamination; Surface reconstruction;
Journal_Title :
Nuclear Science, IEEE Transactions on
