METHODS FOR THE CONTINUOUS DIRECT MEASUREMENT OF RADIOACTIVE SUBSTANCES IN WATER

Journal Article · Mon Oct 01 04:00:00 EDT 1962 · Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech.

OSTI ID:4740777

Gebauer, H; Mueller, S

The detection limits of former monitoring arrangements for the continuous direct measurement of radioactive substances in water were not sufficient to cover most radionucleides in concentrations below the permissible values. At first therefore the method of continuous enrichment and measurement was followed. The introduction of large surface counters for water monitoring on the Karlsruhe nuclear reactor gave fresh impetus to continuous direct monitoring. The methods of direct measurement and reports on the calibration and energy dependence of various arrangements are described. A consideration of the detection limits indicates the activity concentrations which can still be covered. All arrangements of different detectors which are important in practice and have been investigated are described. Detector systems which are in immediate contact with the water have the disadvantage that, in the course of time, the counter surface can easily be contaminated and soiled resulting in an increased background count and an increased absorption of beta radiation. In addition this arrangement with a directly immersed counter has the disadvantage that it cannot deal with low-energy beta radiation because of the large counter wall thickness which is necessary on grounds of stability. If low-energy beta radiation is to be counted the mass of the counter window should not exceed 5 mg/cm/sup 2/. Such thin windows can no longer be immersed in water but the possibility exists of mounting one or more counters on a flow cuvette or of arranging the detectors to be very close to the free surface of the water. For end windows of large area there are no foils which are so gas-tight that the counter filling will not diffuse through them in the course of time. In this case, methane flow counters are used which work in the proportional region and which are continuously flushed with methane as the counter gas. (auth)

• Research Organization: Frieseke and Hoepfner G.m.b.H., Erlangen-Bruck, Ger.
• NSA Number: NSA-17-004815
• OSTI ID: 4740777
• Journal Information: Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech., Journal Name: Atomwirtschaft (West Germany) Changed to ATW, Atomwirtsch., Atomtech. Vol. Vol: 7; ISSN ATWSA
• Country of Publication: Country unknown/Code not available
• Language: German

Related Subjects

ABSORPTION
BACKGROUND
BETA PARTICLES
COUNTERS
ENERGY
ENRICHMENT
FLUID FLOW
FOILS
INSTRUMENTS AND INSTRUMENTATION
MEASURED VALUES
METHANE
MONITORING
PROPORTIONAL COUNTERS
RADIATION DETECTORS
RADIOACTIVITY
RADIOISOTOPES
REACTORS
SURFACES
WATER
WINDOWS