Overview

• According to a parliamentary reply by Defence Procurement Minister Maria Eagle, one Category A event was among 28 nuclear site incidents recorded at HMNB Clyde between January 1 and April 22, 2025.
• Category A denotes incidents with actual or high potential for radioactive release, making it the most serious classification in the Nuclear Site Event Report framework.
• The MoD has argued that releasing operational details would prejudice the capability, effectiveness and security of its nuclear forces.
• Defence Secretary John Healey described the event as of “low safety significance,” adding that it caused no harm to staff or members of the public.
• SNP MPs and investigative reports have seized on the revelation, citing past Category A incidents and radioactive water leaks at RNAD Coulport to press for greater transparency and infrastructure maintenance reforms.