Technical problems relating to furnaces at the UK's nuclear weapons factory used for heating and working with radioactive metals led to a number of incidents with the potential to breach nuclear safety, according to information released to Nuclear Information Service under the Freedom of Information Act.
For each of the two years 2008 and 2009, the Ministry of Defence has revealed that three 'abnormal events' took place at the Atomic Weapons Establishment which had the potential to challenge a nuclear safety system. Four of these six incidents involved problems relating to furnaces in processing buildings at AWE Aldermaston, with the other two relating to a hoist at AWE Burghfield and misconnection of pressure lines in a workstation at AWE Aldermaston.
A request for information about the incidents was submitted by Nuclear Information Service to the Ministry of Defence in March 2010, but the relevant documents (available for download below) were not released by officials until April 2012 – over two years later.
The six abnormal events recorded at AWE took place on the following dates:
23 April 2008: Overheating and temperature control problems during testing of a furnace.
2 April 2008: Switch failed to activate during raising of an electric hoist used to raise nuclear materials at an x-ray facility at AWE Burghfield, causing the hoist to continue to rise beyond its control point.
5 June 2008: Smoke observed inside equipment during operation of a furnace, requiring an emergency response and health physics call out.
7 April 2009: Pressure lines found to be misconnected on a workstation used for the processing of nuclear materials.
20 April 2009: Problems with control limits for the same furnace on two occasions.
15 October 2009: Temperature excursion on a furnace caused by failure of a relay resulting from lack of a maintenance plan for the furnace.
The final incident (15 October 2009) was the result of a formal internal inquiry and the Health and Safety Executive Nuclear Installations Inspectorate was informed of the findings of the inquiry. Action plans for remedying the faults which lead to two of the other incidents were prepared and dealt with under a broader action plan for addressing shortfalls identified under the periodic review of safety for the relevant facility.
Download the incident reports relating to the abnormal events here: