Skip to main content

Nuclear Submarines: Safety

Question for Ministry of Defence

UIN 180428, tabled on 14 April 2023

To ask the Secretary of State for Defence, how many nuclear site events there were at (a) Coulport and (b) Faslane in the last 12 months.

Answered on

20 April 2023

The table below provides the number of Nuclear Site Event Reports (NSERs) at Coulport and Faslane recorded between January 2022 to March 2023. These are shown according to their categorisation using criteria agreed locally in 2015.

Nuclear Site Events- 2022

Category A

Category B

Category C

Category D

Below Scale

Coulport

0

2

7

15

40

Faslane

0

0

20

73

47

Nuclear Site Events- 2023

Category A

Category B

Category C

Category D

Below Scale

Coulport

0

0

2

6

7

Faslane

0

1

6

26

10

In line with Industry Good Practice and in common with other defence and civil nuclear sites, His Majesty’s Naval Base Clyde has a well-established system for raising NSERs.

NSERs are raised to foster a robust safety culture that learns from experience, whether that is equipment failures, human error, procedural failings, documentation shortcoming or near-misses.

The safety significance of all reported events remains low and are below Level 1, the lowest of the seven-point Internal Nuclear and Radiological Event Scale (INES).

None of the events caused harm to the health of any member of staff on the Naval Base or to any member of the public or have resulted in any radiological impact to the environment.