Radiological protection incident at Mafelec (Isère) ASN reclassifies the event to level 2 on the INES scale
ASN was notified on 7th October 2008 by the Isère prefecture of a radiological protection incident that had occurred at Mafelec's Chimilin site relating to radiation emitted by lift buttons manufactured by the company.
ASN had inspected the Mafelec site on the afternoon of 8th October with technical support from the French Institute for Radiological Protection and Nuclear Safety (IRSN) who had taken measurements to identify the levels of exposure.
The incident was provisionally classified by ASN on 8th October as a level 1 event on the INES scale.
ASN has decided to reclassify this event as level 2 on the INES radiological event scale, as more than 10 people within Mafelec were exposed to doses exceeding the regulatory public exposure limit.
ASN is submitting an official report to the Public Prosecutor citing Mafelec as being responsible for several offences relating in particular to the Public Health Code.
ASN has contacted various parties in order to assess the international ramifications of this incident and has taken preventive measures in France.
The ASN inspections
The ASN inspection on 8th October revealed that the packages of goods contaminated with Cobalt-60 arrived on the Mafelec site on 21st August. Furthermore, the reconstitution of doses to which the different workstations are likely to have been exposed revealed that out of the thirty people exposed, twenty or so employees were exposed to doses of between approximately 1 mSv (millisievert) and 3 mSv, levels to be compared with the maximum regulatory exposure limit of 1 mSv/year for the public and workers in the non-nuclear sector.
The ASN inspection on 10th October at Roissy airport, in collaboration with the civil aviation department, determined the exact circumstances of the shipment by Mafelec's freight company of a package of lift buttons contaminated with Cobalt-60. This package was found to be radioactive on 17th September but the fact that the detection gate was triggered was not reported to the authorities. This package was shipped to the USA and was detected on its arrival. A second package of lift buttons contaminated with Cobalt-60 and originating from Mafelec was in the freight zone on the day of the inspection. The inspectors contained the package in an area set aside for radioactive packages. Of 400 packages of this type shipped every year to the USA and routinely inspected, only the two aforementioned packages were found to present anomalies during the radioactivity inspection, which confirms the theory of one-off contamination of metal products from India.
ASN's international contacts
ASN contacted the Nuclear Safety Authorities in the other countries involved to share information on this matter. The Swedish nuclear authority informed ASN of the arrival of contaminated products in Sweden.
In India, the companies BUNTS, LAXMI, SKM STEELS, VIPRAS CASTINGS LTD and PRADEEP METALS LTD were the origin of shipments of products contaminated with Cobalt-60 to several countries. ASN remains in touch with the Indian authority and awaits the results of inspections being carried out on these sites.
ASN activity within OTIS France
ASN is continuing its investigations in France, in particular at OTIS, Mafelec's biggest customer, where measurements on parts from Mafelec have been taken and contaminated parts found, in particular in Roissy, Argenteuil, Goussainville and Gien. Contaminated parts are currently being identified and isolated on all sites in OTIS France's distribution and maintenance network. The levels to which workers in these companies have been exposed are lower than those found at MAFELEC and remain below the regulatory annual exposure limit.
ASN has asked OTIS to cease using all parts that have been identified as contaminated with immediate effect. It has also asked it to carry out an inventory of the contaminated buttons which could have been installed over recent weeks. OTIS has agreed with ASN to carry out the removal and replacement operations required.
ASN has asked MAFELEC not to use lift button components received from India since 1st August 2008. The company has resumed production and delivery of lift buttons using stock received prior to August 2008.
- Consult the Information note of 9 october 2008
- Consult the nuclear event notification of 8 october 2008