Benchmarking Calibration for Low-Level Gamma Spectrometric Measurements of Environmental Samples

Closed for proposals

Project Type

Coordinated Research Project

Project Code

K41011

CRP

1471

Approved Date

19 November 2007

Status

Closed

Start Date

15 August 2008

Expected End Date

14 August 2013

Completed Date

26 November 2013

Description

Development of improved calibration methods and packages is basic to improving the application of gamma spectrometry in environmental radioactivity and radiotracer studies, and to improving comparability of results obtained from different radioanalytical laboratories around the world. The proposed CRP will assist Member State laboratories through development of analytical methodologies and software. Typically, calibrations are carried out using either of two broad approaches: the use of specially prepared standards or by computational means. The computational approach has considerable advantages, especially in terms of the costs which otherwise arise in standard preparation, but there are difficulties which will generally lead to a greater uncertainty in the final calculated efficiencies. Through the CRP the various approaches to calibration will be developed in a complementary way, with careful attention to intercomparability and validation by means of interlaboratory comparison exercises. It is expected that new methods, procedures and software tools of general use to IAEA Member State laboratories will be developed to help laboratories to optimize their detector setup and calibration systems, and to calibrate their systems once set up. The results will be distributed to all countries having an interest in application of gamma spectrometry for environmental radioactivity studies.

Objectives

The CRP overall objective is to assist Member States to co-ordinate the development of validated calibration methods relying on combined experimental and modelling approaches and to establish traceability of results through comprehensive quantification of measurement uncertainties associated with low-level gamma-ray spectrometric analysis of environmental samples.

Specific objectives

To compile and validate software tools, detailed procedures and datasets for calibration of general use to the IAEA Member States laboratories.

To develop improved calibration and efficiency determination methods for widely used types of HPGe detectors, using classical, semi-empirical and computational approaches.

To develop methods to validate and improve the inter-comparability of results obtained with different calibration approaches.

Methods to validate and improve the inter-comparability of results obtained with different calibration approaches.

New and improved calibration and efficiency determination methods for widely used types of HPGe detectors, using classical, semi-empirical and computational approaches.

Software tools and detailed procedures for calibration of general use to the IAEA Member States laboratories.

Impact

Thanks to the close collaboration of CRP participants, 10 peer-reviewed papers were published in scientific journals and computer codes used for advanced gamma spectrometry modelling were benchmarked, improving the understanding of the technical basis of data comparability and reliability. Important metrological aspects were addressed for decay data used, uncertainty budget, reporting of measurement results, including for challenging low-energy, low-activity radionuclides and decay series radionuclides. The CRP helped harmonise the approaches to gamma spectrometric analyses to environmental samples among the participating institutes and further through dissemination in conferences, peer-reviewed scientific papers, 2 MSc theses and a series of workshops and training courses delivered over the years to the ALMERA network and in the framework of regional and interregional TC projects.

Relevance

The reliability and inter-comparability of environmental radioactivity data is essential in both routine and emergency situations, particularly in transboundary contamination events and for networks of laboratories, such as the IAEA's worldwide network ALMERA and national and regional environmental radioactivity monitoring networks. Gamma-ray spectrometry is a common technique, however to obtain reliable analytical results for environmental samples advanced knowledge of gamma-ray spectrometry is required. This CRP has carried out a comprehensive analysis of all the factors that can impact the quality of gamma-ray spectrometric analyses and has proposed approaches to address these.

CRP Publications

Type

peer-reviewed scientific paper

Year

2014

Publication URL

https://reader.elsevier.com/reader/sd/pii/S0969804313004910?token=D99837889C490E…

Description

VIDMAR, Tim et al. Equivalence of computer codes for calculation of coincidence summing correction factors

Country/Organization

5 CRP participants co-authors

Type

Freeware evaluation and application in benchmarking exercise

Year

2009

Description

the EFFTRAN efficiency transfer code

Country/Organization

Slovenia/IJS (RC14894)

Type

peer-reviewed scientific paper

Year

2014

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804313005162

Description

Suvaila, R. et al. Improved method for the assessment of 60Co and 134Cs point sources in samples with non-homogeneous matrix. Applied Radiation and Isotopes 87 (2014) 384–386

Country/Organization

CRP collaboration

Type

peer-reviewed scientific paper

Year

2013

Publication URL

https://inis.iaea.org/Search/search.aspx?orig_q=RN%3A45112563

Description

SIMA , O. et al. Calibration of a low-level anti-Compton underground gamma-spectrometer by experiment and Monte-Carlo, Applied Radiation and Isotopes 81(2013), 109–113

Country/Organization

CRP collaboration

Type

peer-reviewed scientific paper

Year

2012

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804312001273

Description

LEPY, M-C. et al.. Intercomparison of methods for coincidence summing corrections in gamma-ray spectrometry. Part II. Appl. Radiat. Isotopes, 2012, vol. 70, no. 9, p. 2112-2118

Country/Organization

4 CRP participants co-authors

Type

peer-reviewed scientific paper

Year

2011

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804311001357

Description

VIDMAR, Tim, KANISCH, Gunter, VIDMAR, Gaj. Calculation of true coincidence summing corrections for extended sources with EFFTRAN. Appl. Radiat. Isotopes, 2011, vol. 69, no. 6, p. 908-911

Country/Organization

Slovenia/IJS (RC14894)

Type

peer-reviewed research paper

Year

2010

Description

J. Carrazana et al. “The effect of source chemical composition on the self-attenuation corrections for low-energy gamma-rays in soil samples”. Appl. Radiat. Isot. 68 (2010) 360–363.

Country/Organization

Cuba/Centro de Protection e Higiene de las Radiaciones

Type

peer-reviewed scientific paper

Year

2010

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804310002290

Description

VIDMAR, Tim, VODENIK, Branko, NECEMER, Marijan. Efficiency transfer between extended sources. Appl. Radiat. Isotopes, 2010, vol. 68, p. 2352-2354

Country/Organization

Slovenia/IJS (RC14894)

Type

peer-reviewed scientific paper

Year

2010

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804309006290?via%3Dihub

Description

T. Vidmar et al. Testing efficiency transfer codes for equivalence. Appl. Rad. Isot. 68 (2010) 355–359J.

Country/Organization

collaboration of 7 CRP participants

Type

peer-reviewed scientific paper

Year

2010

Publication URL

https://reader.elsevier.com/reader/sd/pii/S0969804309006307?token=BFC39403984EB9…

Description

J. Carrazana Gonzalez et al. The effect of source chemical composition on the self-attenuation corrections for low-energy gamma-rays in soil samples. Appl. Rad. Isot. 68 (2010) 360-363

Country/Organization

Cuba/CPHR (RC 14378)

Type

conference presentation, published later in peer-reviewed scientific journal

Year

2013

Publication URL

https://www.sciencedirect.com/science/article/pii/S0969804315303055

Description

VIDMAR, Tim, et al. Equivalence of computer codes for calculation of coincidence summing correction factors. ICRM 2013, Antwerp

Country/Organization

4 CRP participants co-authors

Type

peer-reviewed scientific paper

Year

2010

Description

T. Vidmar et al. “Testing efficiency transfer codes for equivalence”. Appl. Radiat. Isot. 68 (2010) 355–359.

Country/Organization

Collaborative paper initiated by RA holder T. Vidmar and co-authored with CRP participating institutes

Type

peer-reviewed research paper

Year

2012

Description

J. Carrazana et al. “Application of the Monte Carlo code DETEFF to efficiency calibrations for in situ gamma-ray spectrometry”. Appl. Radiat. Isot 70(5) (2012) 868-71.

Country/Organization

Cuba/Centro de Protection e Higiene de las Radiaciones

Stay in touch

Newsletter