R. Cruz-Suarez

AIDE: internal dosimetry software.

AIDE (Activity and Internal Dose Estimates) is a software for calculating activities in compartments and committed doses due to occupational exposures, and for performing intake and dose estimates using bioassay data. It has been continuously developed and tested for more than 20 years. Its calculation core has been applied in several situations, like performing all dose estimates due to (137)Cs intakes, which occurred during the Goiania accident in 1987; performing quality assurance of the ICRP Task Group on Dose Calculations regarding calculations of activities in compartments and generation of dose coefficients for adults due to intakes by inhalation, ingestion and injection of several radionuclides; and producing the tables of activities in compartments and dose coefficients using the NCRP Wound Model for the NCRP report. It provides several capabilities like performing calculations using modified Human Respiratory Tract Model parameters for the mechanical transport, blood absorption and partitions of deposit in the AI region. The existing systemic models can also be modified or new ones can be entered. All estimate procedures are in accordance with the methods presented in the ICRP-78 Publication, in the IAEA Safety Reports Series no. 37 and in the IDEAS Project Guidelines 2006.

International project on individual monitoring and radiation exposure levels in interventional cardiology

Within the Information System on Occupational Exposure in Medicine, Industry and Research (ISEMIR), a new International Atomic Energy Agency initiative, a Working Group on interventional cardiology, aims to assess staff radiation protection (RP) levels and to propose an international database of occupational exposures. A survey of regulatory bodies (RBs) has provided information at the country level on RP practice in interventional cardiology (IC). Concerning requirements for wearing personal dosemeters, only 57 % of the RB specifies the number and position of dosemeters for staff monitoring. Less than 40 % of the RBs could provide occupational doses. Reported annual median effective dose values (often <0.5 mSv) were lower than expected considering validated data from facility-specific studies, indicating that compliance with continuous individual monitoring is often not achieved in IC. A true assessment of annual personnel doses in IC will never be realised unless a knowledge of monitoring compliance is incorporated into the analysis.

EURADOS intercomparison on emergency radiobioassay

Nine laboratories participated in an intercomparison exercise organised by the European Radiation Dosimetry Group (EURADOS) for emergency radiobioassay involving four high-risk radionuclides ((239)Pu, (241)Am, (90)Sr and (226)Ra). Diverse methods of analysis were used by the participating laboratories for the in vitro determination of each of the four radionuclides in urine samples. Almost all the methods used are sensitive enough to meet the requirements for emergency radiobioassay derived for this project in reference to the Clinical Decision Guide introduced by the NCRP. Results from most of the methods meet the requirements of ISO 28218 on accuracy in terms of relative bias and relative precision. However, some technical gaps have been identified. For example, some laboratories do not have the ability to assay samples containing (226)Ra, and sample turnaround time would be expected to be much shorter than that reported by many laboratories, as timely results for internal contamination and early decisions on medical intervention are highly desired. Participating laboratories are expected to learn from each other on the methods used to improve the interoperability among these laboratories.

EURADOS IC2012N: EURADOS 2012 intercomparison for whole-body neutron dosimetry

The European Radiation Dosimetry Group (EURADOS) IC2012n intercomparison for neutron dosemeters intended to measure personal dose equivalent, Hp(10), was performed in 2012. A total of 31 participants (27 individual monitoring services from Europe, 2 from Japan, 1 from Israel and 1 from USA) registered with 34 dosimetry systems. Participation was restricted to passive or active neutron dosemeters routinely used in individual monitoring of radiation workers. The dosimetry systems were based on thermoluminescence, polyallyldiglycol carbonate, optically stimulated luminescence, fission track detection and silicon diodes (electronic devices). The irradiation tests were chosen to provide the participants with useful information on their dosimetry systems, i.e. linearity, reproducibility, responses for different energies and angles and to simulated workplace fields. The paper will report and discuss the first analysis of the results of the EURADOS IC2012n intercomparison.

IAEA regional intercomparison of in vivo measurements of 131I in the thyroid: the Latin American and Caribbean experience

An in vivo intercomparison exercise, organised in the scope of the IAEA Regional Latin American (RLA) Project 9066, was carried out in 2009 aimed to harmonise measurement procedures on the measurement of (131)I in the thyroid among Latin American and Caribbean countries. The exercise consisted in the measurement of an anthropomorphic thyroid phantom spiked with a certified source of (133)Ba. The phantom was supplied by the In Vivo Monitoring Laboratory of Institute for Radiation Protection and Dosimetry (IRD) to 17 Institutions from 12 countries of the regions. Among these, 13 Institutions from 10 countries returned their measurement results as well as a standard report form containing detailed information about their respective counting facilities. All participants reported activities within an acceptable range, considering American National Standard Institute (ANSI) limits. Uncertainties varied from 0.04 to 12.9 %. Although results show that the general performance was acceptable in terms of accuracy, the need for additional action towards the standardisation of uncertainty estimation in this type of measurement in the region should be highlighted.

Radiation protection for pregnant workers and their offspring: a recommended approach for monitoring

Radiation protection of pregnant workers and their offspring is an issue that has been referenced in the literature by the International Commission on Radiological Protection (ICRP), the International Atomic Energy Agency (IAEA) and other international institutions. Several documents of the ICRP address the issue of the protection of the pregnant workers. The new ICRP recommendations refer to the control of working conditions of a pregnant worker, after declaration of pregnancy, such that it is unlikely that the additional dose to the fetus will exceed about 1 mSv during the remainder of pregnancy. The IAEA Basic Safety Standards present similar recommendations. The IAEA is preparing a technical document that provides guidance on these issues.

EURADOS IC2012N: FURTHER INFORMATION DERIVED FROM AN EURADOS INTERNATIONAL COMPARISON OF NEUTRON PERSONAL DOSEMETERS

In 2012, the European Radiation Dosimetry Group (EURADOS) performed an intercomparison for neutron dosemeters that are intended to measure personal dose equivalent, Hp(10). A total of 31 participants registered with 34 dosimetry systems. The irradiation tests were chosen to provide the participants with useful information on their dosimetry systems, i.e. linearity, reproducibility, responses for different energies and angles and to simulated workplace fields. This paper gives details of the extensive information derived from the exercise.

IAEA INTERCOMPARISON EXERCISES OF THYROID MEASUREMENT: PERFORMANCE OF LATIN AMERICAN AND CARIBBEAN LABORATORIES

(131)I is widely used in Latin America and Caribbean Region in the field of nuclear medicine and has been recognised as one of the main sources of potential intake of radionuclides by the staff. The In Vivo Monitoring laboratory of the Institute for Radiation Protection and Dosimetry (IRD-CNEN-Brazil) organised three intercomparison exercises (2005, 2009 and 2013) in the scope of IAEA technical cooperation projects RLA9049 and RLA9066 aimed to disseminate and harmonise the technique for measuring (131)I in the human thyroid. The number of participants in Latin America increased from 9 to 20 institutions from 7 and 13 countries, respectively, over the last 10 y. The participants have improved significantly their ability on the in vivo measurement technique. In the 2013 round all laboratories which reported results presented performances in an acceptable range according to the ISO criteria indicating the benefit of such exercises in the region.

Intercomparison on measurements of the quantity personal dose equivalent Hp(10) in photon fields in the African region

An intercomparison was arranged by the International Atomic Energy Agency for the African region for personal dose equivalent. This was arranged with a view to helping member states to comply with dose limitation requirements and to harmonise the use of internationally agreed quantities and recommended assessment methods. The scope of the intercomparison was aimed at passive dosemeters, which determine the personal dose equivalent in photon radiation fields. The comparison protocol is presented together with the results.

Individual and workplace monitoring measurements made after a 240Pu incident and during the clean-up operations.

On 3 August 2008, five glass vials containing around 7 GBq of (240)Pu in nitric acid solution burst in a laboratory operated by the IAEA in Seibersdorf, Austria. The vials were located in a fire-proof safe in the IAEA Safeguards Analytical Laboratory, and the release of the (240)Pu caused an air contamination in the room and in adjoining rooms. Immediate emergency work was carried out, which was then followed by a long period of clean-up operations. A large number of conventional individual and workplace monitoring measurements were carried out immediately after the incident and during the clean-up work. In addition, due to the fact that (240)Pu has a very low background presence in the environment, and that the IAEA laboratories operate an inductively coupled plasma mass spectrometry system capable of very low levels of detection of this radionuclide, a number of non-conventional measurements were made to detect (240)Pu on, for example, the photographic camera used to document the incident, on nasal swabs from the first responders, etc. Plastic beakers were left in the corridor of the controlled area to accumulate (240)Pu from precipitation to see whether it was possible to detect traces of the radionuclide. This paper presents the measurements obtained, and discusses their relevance to occupational radiation protection.