ASN has reclassified to level 2 the incident which occurred on 19 November 2009 in the irradiated fuel reprocessing plant (UP2 400) on the site at La Hague

Internal contamination of an employee from a subcontracting company

On March 24, following a proposal by the operator, ASN reclassified to level 2 on the INES scale ^[1], the incident which occurred on 19 November 2009 in the MAU (Intermediate Level Uranium) workshop of nuclear facility no. 33, known as UP2-400, on the AREVA NC site at La Hague.

On 19 November 2009, an employee from a subcontracting company was contaminated, notably by plutonium, during a dust removal operation in a sub-unit of the MAU workshop. Although whilst working he was equipped with a ventilated protective suit , his right hand struck a metal wire which was used to hold an identification label on a pipe located in the sub-unit. The metal wire pierced the employee's safety gloves and pricked him, leading to his internal contamination. The operator has carried out a detailed analysis of the incident which is being examined by ASN. The operator has temporarily suspended this type of cleaning operation in the workshop in order to redefine the working procedures and to improve the procedures for use of individual protective equipment.

The results of additional examinations, carried out periodically on the contaminated employee, led to an evaluation of the committed effective dose over 50 years ^[2] at a value which lies between 20 mSv and 100 mSv ^[3]. This dose was assessed by the occupational health physician and confirmed by the Institute for Radiological Protection and Nuclear Safety (IRSN). No pathology has been observed to date for this level of exposure.

In view of the level of exposure of the employee, the incident has been reclassified to level 2 on the INES Scale, following the criteria of this international scale.

The MAU workshop belongs to the first reprocessing plant, UP2-400, at La Hague, site which is now shut down. Historically, the industrial function of the MAU workshop consisted of separating uranium from plutonium contained in a nitric acid solution and then purifying the uranium.

Press contact: Evangelia Petit, Press Relations Manager, tel. +33 (0)1 40 19 86 61 evangelia.petit@asn.fr

[1] The INES scale (International Nuclear and Radiological Event Scale) is a scale for communicating the seriousness of incidents concerning nuclear safety and radiological protection. It consists of 8 levels, numbered from 0 to 7, from the least serious to the most serious respectively.

[2] The "committed effective dose over 50 years" corresponds to the total integrated dose over a period of 50 years, by considering the largest and smallest "transferability" of radioisotopes in biological tissues as well as their radioactive half-life. It therefore corresponds to a calculation of the impact of the contamination incident over the individual’s entire life. The legal annual dose limit for a worker is set at 20 mSv.

[3] The exact value of the dose cannot be revealed because of questions of medical confidentiality.