Dear valued customers,

We are pleased to announce that the registration for IARMA proficiency tests is now open. As a UK-based company, we offer proficiency testing for laboratories worldwide. Our tests are designed to assess your laboratory’s proficiency in environmental radioactivity, including  four (4) proficiency tests:

1- ERAD on the determination of natural and anthropogenic radionuclides in Hay and drinking water.

2- EGROSS on the measurement of gross alpha/beta activities in drinking and seawater.

3- ETRIT on the determination of tritium in water at an environmental level.

4- ECARB on the determination of Carbon-14 in water at an environmental level.

We invite you to participate in our upcoming proficiency tests to demonstrate your laboratory’s capabilities and ensure that your results are accurate and reliable. Our tests are carefully designed to assess your laboratory’s competence in various areas, and we provide a certificate of participation as a piece of evidence.

To register for the ERAD, EGROSS, ETRIT and ECARB proficiency tests, please use the links listed above and follow the registration process. Our team will be happy to assist you with any questions or concerns you may have.

We look forward to your participation in our proficiency tests and helping you achieve your laboratory’s quality goals.

Best regards,


Dear IARMA Costomers,

We are pleased to announce the release of the final IARMA Proficiency Test Reports! Your feedback is invaluable to us, and we will consider it to enhance your experience.

We have incorporated valuable insights and comments from participants to provide you with even more accurate and comprehensive proficiency test reports.

To Access Your Reports, please Log in to your IARMA Portal and download your updated report.

Thank you for being a part of the IARMA community. We look forward to serving you with enhanced proficiency test.

Best regards,

The IARMA Team

Dear IARMA Customers,

We are pleased to inform you that the draft reports for the 2023 proficiency tests are now available for download from the IARMA customer portal. To access the draft reports, please follow these steps:

These draft reports offer a comprehensive overview of your laboratory’s performance in the proficiency tests, allowing you to review and analyze the results. Your feedback on the draft reports is valuable to us, and we encourage you to provide any comments or observations by 17 January 2024.

If you encounter any issues or have questions regarding the draft reports, please do not hesitate to reach out to our customer support team.

Thank you for your continued partnership with IARMA. Your dedication to quality assurance contributes to the overall success of proficiency testing programs. We look forward to receiving your registration on the next Proficiency Test Scheme which starts on 15 March 2024.

Dear IARMA Community,

The participant recognised that the value of participation as it goes far beyond achieving reliable results; it serves as an opportunity for continual improvement and a demonstration of their technical competence to deliver remarkable outcomes that support quality management system of the organization. The participating laboratory highlighted the achievement of an improvement in their performance year after year.

IARMA Team appreciates the participation and dedication of all participating laboratories for excellence in environmental radioactivity testing.

Many thanks for your continued support and collaboration wishing you all the best for the festivity season.

Best regards,


Dear IARMA Participants,

IARMA is committed to facilitating a smooth experience for all participants.

Taking into consideration the complexities that can occur during the analysis, and in light of recent feedback from you, we are pleased to announce an extension to the deadline for the Proficiency Test Results Reporting.

The new deadline is now set for November 20, 2023, to ensure that everyone has sufficient time to submit their results without undue pressure.


Proficiency tests (PT) are becoming a fundamental tool for labs to externally validate and assess the quality of their results. This article explores into the complexities of selecting the right PT and how labs can impact PT providers. Equally, it asks the question if PT providers have responsibilities beyond simply supplying test items and performance reports to laboratories.

This article is highlighting the case of IARMA (International Atomic Reference Material Agency), and offers some insights on IARMA’s Journey: IARMA establishment in 2013, IARMA’s impact in numbers and its customer-centric approach.

Full article

Dear Participants of the IARMA Proficiency Tests,

We are pleased to inform you that the shipment of the test items packages for the upcoming 2023 IARMA Proficiency Tests has been successfully completed. Your dedication to quality assurance and proficiency is greatly appreciated, and we are excited to embark on this testing journey with you.


Dear Valued Analytical Laboratories,

IARMA is offering a unique opportunity to enhance your laboratory’s proficiency in environmental radioactivity. Our UK-based company has designed four key tests:

  1. ERAD: Natural and Anthropogenic Radionuclides in soil and water.
  2. EGROSS: Gross Alpha/beta activities in water.
  3. ETRIT: Tritium in water.
  4. ECARB: Carbon-14 in water.


Join labs worldwide in demonstrating your capabilities and commitment to quality. Click Register to participate in our upcoming tests and receive a certificate of participation.
Deadline for registration: 01 July 2023.


Dear Valued Customers,

IARMA has recently released the final reports of the Proficiency Tests ERAD, EGROSS, and ETRIT for the cycle 2022. These tests were conducted to evaluate the analytical capabilities of laboratories in accurately determining natural and anthropogenic radionuclides, gross alpha/beta, and tritium in both water and mushrooms.

By participating in these proficiency tests, laboratories gain valuable independent evidence of their performance. The reports provide detailed insights into the strengths and weaknesses of their analytical processes, allowing them to identify and address any shortcomings that may have been detected.

The final reports not only present the results of the ERAD, EGROSS, and ETRIT proficiency tests for the cycle 2022 but also outline the methodologies and data evaluation approaches employed. This comprehensive information ensures transparency and helps laboratories understand the evaluation criteria used during the tests.

It is worth noting that the preparation and characterization of the proficiency test items were carried out in collaboration with esteemed institutions such as the Józef Stefan Institute (Slovenia) and the Environmental Research Institute (UK). This collaboration ensures the credibility and quality of the proficiency tests, providing laboratories with reliable benchmarks for their performance assessment.

IARMA offers convenient access to the final reports through the Customer Portal. Laboratories participating in the proficiency tests can easily download the reports from the portal, allowing them to review the detailed findings and recommendations. This user-friendly approach ensures that the valuable information contained within the reports is readily accessible to all participating laboratories for long time.

After the conclusion of the IARMA ERAD-PT-2022 Proficiency Test, a valuable feedback was received from a participant regarding a common challenge faced by multiple participants when attempting to determine Pb-210 in the presence of Eu-152 in the IARMA-137 Mushroom Test Item. This feedback shed light on an issue that hindered accurate measurements and called for further investigation. In this post, we dip into the difficulties of this challenge, explore the complexities associated with the interference of Eu-152, and present the analytical approaches taken to overcome this obstacle. By sharing these insights, we aim to enhance the understanding of Pb-210 analysis in the presence of Eu-152, offering valuable guidance for future assessments in similar scenarios.

The determination of the massic activity of Pb-210 in the mushroom sample IARMA-137 presented challenges due to the significant activity of Eu-152, which was also present in the sample.

Specifically, there were two energy lines of Eu-152 that were close to the 46.5 keV energy line of Pb-210. These energy lines corresponded to the X-ray lines of Sm-152, which is the daughter product of Eu-152. The X-ray lines, Kβ1 and Kβ2, had energies of 45.4 keV and 46.7 keV, respectively. If the spectrometer had good enough resolution, the Kβ1 line could be subtracted through proper deconvolution of the doublet at 45.4 keV and 46.5 keV. However, the Kβ2 line of Eu-152 at 46.7 keV completely overlapped with the gamma line of Pb-210 at 46.5 keV. Therefore, it was necessary to correct the calculated activity of Pb-210 for the interference caused by Eu-152 at 46.7 keV, which was not done in the automatic analysis procedure.

Multiple measurements were conducted using various spectrometers. The second column of Table 1 presents the individual results for the massic activity of Pb-210 obtained through automatic analysis and deconvolution of the doublet at 45.4 keV and 46.5 keV. The average value and combined uncertainty are also reported in the green set of data as shown in the Table below.

Table 1: The individual results for the massic activity of Pb-210

Upon receiving the evaluation report from IARMA, it became evident for the participant that the result for Pb-210 was not acceptable, with a relative bias of 78.9% and a Z-test of 7.9.

To address this discrepancy, further analyses were performed. Initially, the doublet at 45.4 keV and 46.5 keV was manually resolved to verify the results of the automatic analysis and the reported values. The manually obtained results, shown in the third column of Table 1 (violet set of data), were slightly lower but still consistent with the reported value within the uncertainty. However, in this analysis, the contribution of the Kβ2 line was not subtracted from the line at 46.5 keV.

In the second attempt, the contribution of Eu-152 at 46.7 keV was subtracted from the remaining Pb-210 area at 46.5 keV. This interference was not corrected during the automatic analysis procedure.

The final results, presented in the fourth column (orange set of data), confirmed that the calculated values for the massic activity of Pb-210 were systematically too high due to the incomplete resolution of the interference between Pb-210 and Eu-152 at the energy lines of 46.5 keV and 46.7 keV, respectively. It is worth mentioning that coincidence summing corrections for the 46.7 keV line of Eu-152 were separately calculated using the EFFTRAN efficiency transfer program.

The final corrected result for Pb-210 was determined to be (16.60 ± 3.74) Bq/kg, which agreed with the reference value (18.0 ± 0.54) Bq/kg, with a relative bias of -7.8% and a ζ-test of 0.37.

Based on this analysis, it can be concluded that when the massic activity of Eu-152 is comparable to or greater than the massic activity of Pb-210, evaluating the specific activity of Pb-210 solely from the line at 46.5 keV is challenging, as the contribution of the Kβ2 line of Sm-152 is not negligible and must be taken into account.

If you have experienced similar challenges or have feedback to share regarding the determination of Pb-210 in the presence of Eu-152 in the IARMA-137 Mushroom Test Item, we would appreciate your contact. Your insights are valuable, and together we can enhance our understanding of this complex issue. Please reach out to us with your feedback.