Level-2 incident at Bordeaux University: discovery of radioactive sources and incidental exposure of persons

On 18 September 2015, Bordeaux University - Carreire Campus - informed ASN of the discovery of two radioactive sources in a room in the INSERM laboratory.

The laboratory in question has not had a license to hold radioactive sources for many years now due to the cessation of its activities involving radioactive sources.

The two radioactive sources were discovered by the Bordeaux University prevention service in a very cluttered and regularly frequented room during a housekeeping operation carried out at the end of June 2015.

As soon as they were discovered, the sources were transferred for safe storage in a room specially intended for that purpose within the university campus.

On 4 September the university's radiation protection service conducted an inspection to determine the radiological characteristics of the retrieved sources. Risks of irradiation and contamination were evidenced around one of the two sources. It is an unidentified source displaying a dose rate of 3.4 mSv/h on contact.

The radiological inspection of the room did not reveal any radioactive contamination.

On the other hand, according to the first received dose estimates, a person working in this room would have received a dose approaching 20 mSv/year and several others would have received a dose slightly higher than the annual regulatory limit set for the general public (1 mSv).

ASN carried out an inspection at Bordeaux University on 1 October 2015 to examine the circumstances of this event (refer to the inspection follow-up letter). Further to this inspection, ASN asked that an action plan be engaged to prevent a similar event occurring again, and that an estimate be made of the effective doses received by all the personnel that could have been exposed to the ionising radiation.

The shortcomings in the radiation protection culture and the dose potentially received by the exposed persons has led ASN to rate this event level 2 on the INES scale, which comprises 8 levels from 0 to 7.