Criticality accident dosimetry systems: an international intercomparison at the silene reactor in 2002

Abstract

In criticality accident dosimetry and more generally for high dose measurements, special techniques are used to measure separately the gamma ray and neutron components of the dose. To improve these techniques and to check their dosimetry systems (physical and/or biological), a total of 60 laboratories from 29 countries (America, Europe, Asia) participated in an international intercomparaison, which took place in France from 9 to 21 June 2002, at the SILENE reactor in Valduc and at a pure gamma source in Fontenay-aux-Roses. This intercomparison was jointly organised by the IRSN and the CEA with the help of the NEA/OCDE and was partly supported by the European Communities. This paper describes the aim of this intercomparison, the techniques used by the participants and the two radiation sources and their characteristics. The experimental arrangements of the dosemeters for the irradiations in free air or on phantoms are given. Then the dosimetric quantities measured and reported by the participants are summarised, analysed and compared with the reference values. The present paper concerns only the physical dosimetry and essentially experiments performed on the SILENE facility. The results obtained with the biological dosimetry are published in two other papers of this issue.

Review of retrospective dosimetry techniques for external ionising radiation exposures

“…For the above techniques, procedures and protocols have been established for several decades and some countries offer the possibility of regular training of interventional teams and medical analysis laboratories (106) .…”

Response of radiophotoluminescent dosimeters to neutrons

“…This detector is often used for gamma ray dose measurements in mixed field dosimetry, especially for criticality accidents (Médioni et al, 2004;Miljanić et al, 2007a). The comparison is shown in Table 2.…”

Early-response multiple-parameter biodosimetry and dosimetry: risk predictions

“…There are on-going efforts to optimize and validate these methods for applied biodosimetry applications. In the special case of criticality accidents, neutron activation is used to detection of neutron dose, typically at reactor facilities [80].…”

“…Radiation dose to unspecified locations on the body, when in fact it may not be homogeneous, may not be useful for predicting risk. Use of a multi-parameter biodosimetry approach for EPR Nails (ex vivo) EPR X-band shows a lower limit of detection of 0.5-1 Gy [108][109][110][111] Teeth (in vivo) EPR L-band is potentially able to measure doses as low as 2 to 3 Gy but needs additional development [112][113][114][115][116] Ultrasound and thermography Ultrasound, thermography On-going studies evaluating use of ultrasound combined with thermography to characterize thickness of radiation-induced thermal burn [117][118][119][120][121][122][123] Neutron activation Neutron activation Assessment of neutron dose based on neutron-induced activation on-going at nuclear centres with risk of criticality accidents [80,[124][125][126][127] radiation dose and injury assessment is recommend for incidents involving life-threatening exposures [128]. The combined use of traditional biological-, clinical-, and physical-dosimetry (with location body-specific doses) should be use in an integrated approach to provide: (a) early-phase diagnostics to guide the development of initial medical management strategy, and (b) intermediate and definitive assessment of radiation dose and injury.…”