Question to the Ministry of Defence:
To ask the Secretary of State for Defence, how many nuclear safety events there were at HMNB Clyde and RNAD Coulport involving (a) Class A and (b) Class B incidents involving (i) nuclear propulsion and (ii) nuclear weapons; and what the details were of each such incident.
The information requested, accompanied by the category definitions, is provided below.
Events are categorised in accordance with Her Majesty's Naval Base Clyde's internal criteria, which record all events, however seemingly minor. This comprehensive, independent recording process allows Clyde to maintain a robust reporting culture, undertake learning from experience and to take early corrective action. This reporting process has been agreed by, and is subject to routine inspections by, the Defence Nuclear Safety Regulator.
None of the events in the reports caused any harm to the health of any member of staff on the Naval Base, or to any member of the public, and the severity of the reported events has remained at a very low level. For example, incorrect labelling of an empty pallet and not filling out the correct form before painting inside a submarine are two of the recorded events. Investigations into all such events are carried out and, where necessary, measures are, put in place to prevent a recurrence.
Nuclear safety events involving Nuclear Propulsion:
FY 2008-09 | FY 200910 | FY 2010-11 | FY 2011-12 | FY 2012-13 | FY 2013-14 | TOTAL | |
Category A | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Category B | 9 | 0 | 2 | 0 | 1 | 0 | 12 |
Category C | 32 | 31 | 21 | 26 | 31 | 45 | 186 |
Category D | 32 | 27 | 35 | 27 | 25 | 54 | 200 |
TOTAL | 73 | 58 | 58 | 53 | 57 | 99 | 398 |
Nuclear safety events involving Nuclear Weapons:
FY 2008-09 | FY 2009-10 | FY 2010-11 | FY 2011-12 | FY 2012-13 | FY 2013-14 | TOTAL | |
Category A | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Category B | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Category C | 1 | 1 | 0 | 0 | 1 | 0 | 3 |
Category D | 1 | 12 | 14 | 7 | 10 | 6 | 50 |
TOTAL | 2 | 13 | 14 | 7 | 11 | 6 | 53 |
There were no Category A or Category B events involving Nuclear Weapons, nor any Category A events involving Nuclear Propulsion. The details of the twelve Category B incidents involving Nuclear Propulsion are as follows:
Date | Description |
11 May 2008 | Low level contamination detected on the discharge pipework within the Radioactive Effluent Disposal Facility.
|
9 June 2008 | Temporary shielding to a valve in the Reactor Compartment had been removed without correct authorisation.
|
27 June 2008 | Inadvertent draining of onboard chemically treated water tanks into the contained submarine bilge, with no loss of water into the environment.
|
9 July 2008 | A crane at the berth was operated in a non-standard configuration without an approved concession.
|
2 October 2008 | Radiography Testing using a Faulty Source Mechanism.
|
27 October 2008 | A diving operation was undertaken while the reactor was operational.
|
8 December 2008 | Inadvertent shutting of steam valves out-with normal operating procedures.
|
11 February 2009 | Explosives Handling Jetty (EHJ) 125 tonne crane - lifts total breached. While within the capacity of the crane, the number of lifts exceeded the agreed annual total.
|
20 March 2009 | EHJ 125 tonne crane - lifts total breached. Following the previous incident, a concession was granted, however, this was subsequently exceeded for operational support purposes.
|
12 June 2010 | Loss of a freeze seal during routine valve maintenance leading to a contained submarine compartment water spill, with no loss of water into the environment.
|
14 June 2010 | Used protective suits in a double-layered plastic bag were accidentally dropped into the waters in the Base and recovered immediately. A member of staff became wet when recovering them: as a precaution, he was monitored to ensure no contamination, and was given the all clear.
|
17 August 2012 | Inadvertent radiation dose received by contractors while conducting submarine tank defect rectification work.
|
HM NAVAL BASE CLYDE - NUCLEAR SAFETY EVENT REPORTING
CATEGORY DEFINITIONS
Cat |
Nuclear Event Consequence |
Description
|
A | Actual or high potential for radioactive release to the environment or over exposure to radiation. | · Major failure of Site or Nuclear Propulsion/Nuclear Weapon (NP/NW) services.
· Major reduction of defence in depth.
· Major failure in administrative controls or regulatory compliance. |
B | Actual or high potential for a contained release within building or submarine or unplanned exposure to radiation.
| |
C | Moderate potential for future release or exposure, or localised release within a designated radiological controlled area. | · Minor failure of Site or NP/NW services (eg with protection via defence in depth).
· Minor regulatory or procedural compliance breach.
|
D | Low potential for release – but may contribute towards an adverse trend producing latent conditions. | · Poor safety culture, eg:
- Failure to report shortfalls. - Communication failures. - Leadership issues.
|