BS EN ISO 18589-7:2016

Foreword
Introduction
1 Scope
2 Normative references
3 Terms, definitions, symbols, and units
4 Principles
5 Equipment
6 Procedure
7 Quality assurance and quality control program
8 Expression of results
9 Test report
Annex A (informative) - Influence of radionuclides in air on
        the result of surface or mass activity measured
        by in situ gamma spectrometry
Annex B (informative) - Influence quantities
Annex C (informative) - Characteristics of germanium detectors
Annex D (informative) - Field-of-view of an in situ gamma
        spectrometer as a function of the photon energy for
        different radionuclide distributions in soil
Annex E (informative) - Methods for calculating geometry
        factors and angular correction factors
Annex F (informative) - Example for calculation of the
        characteristic limits as well as the best estimate
        of the measurand and its standard uncertainty
        of the measurand and its standard uncertainty
Annex G (informative) - Conversion factors for surface or
        mass activity to air kerma rate and ambient dose
        equivalent rate for different radionuclide distribution
        in soil
Annex H (informative) - Mass attenuation factors for soil
        and attenuation factors for air as a function of photon
        energy and deviation of G(E,V) for different soil
        compositions
Bibliography

Gives the identification of radionuclides and the measurement of their activity in soil using in situ gamma spectrometry with portable systems e quipped with germanium or scintillation detectors.

This part of 18589 specifies the identification of radionuclides and the measurement of their activity in soil using in situ gamma spectrometry with portable s ystems e quipped with germanium or scintillation detectors.

This part of ISO 18589 is suitable to rapidly assess the activity of artificial and natural radionuclides deposited on or present in soil layers of large areas of a site under investigation.

This part of ISO 18589 can be used in connection with radionuclide measurements of soil samples in the laboratory (ISO 18589-3) in the following cases:

• routine surveillance of the impact of radioactivity released from nuclear installations or of the evolution of radioactivity in the region;

• investigations of accident and incident situations;

• planning and surveillance of remedial action;

• decommissioning of installations or the clearance of materials.

It can also be used for the identification of airborne artificial radionuclides, when assessing the exposure levels inside buildings or during waste disposal operations.

Following a nuclear accident, in situ gamma spectrometry is a powerful method for rapid evaluation of the gamma activity deposited onto the soil surface as well as the surficial contamination of flat objects.

NOTE The method described in this part of ISO 18589 is not suitable when the spatial distribution of the radionuclides in the environment is not precisely known (influence quantities, unknown distribution in soil) or in situations with very high photon flux. However, the use of small volume detectors with suitable electronics allows measurements to be performed under high photon flux.