Foreword

Hauptteil

1Scope

2Normative references

3Terms and definitions

4Symbols

5Principle

6Reference sources

6.1Source(s) for energy calibration

6.2Reference source(s) for efficiency calibration

6.2.1General

6.2.2Reference sources for laboratory systems

6.2.3Reference sources used with numerical methods

7Reagents

8Gamma-ray spectrometry equipment

8.1General description

8.2Detector types

8.3High voltage power supply

8.4Preamplifier

8.5Cryostat or electric cooler

8.6Shielding

8.7Analogue or digital acquisition electronics

8.7.1General

8.7.2Analogue electronic (ADC)

8.7.3Digital electronic (DSP)

8.8Computer, including peripherical devices and software

9Nuclear decay data

10Sampling

11Procedure

11.1Sample preparation

11.1.1General

11.1.2Direct measurement without preparation

11.1.3Evaporation without iodine retention

11.1.4Evaporation with iodine retention

11.2Calibration

11.2.1General

11.2.2Energy calibration

11.2.3Efficiency calibration

12Expression of results

12.1Calculation of the activity concentration

12.1.1General

12.1.2Dead time and pile up corrections (see )

12.1.3Decay corrections

12.1.4True coincidence summing

12.1.4.1General

12.1.4.2Probability of true-coincidence summing

12.1.4.3Consequences for source-based efficiency calibrations and for sample count

12.1.4.4Reducing the effect of true-coincidence summing

12.2Standard uncertainty

12.3Decision threshold

12.4Detection limit

12.5Limits of the coverage intervals

12.5.1Limits of the probabilistically symmetric coverage interval

12.5.2The shortest coverage interval

12.6Corrections for contributions from other radionuclides and background

12.6.1General

12.6.2Contribution from other radionuclides

12.6.3Contribution from background

13Test report