Nuclear Test Veteran Records Exercise and the Merlin Database

Monday 30th June 2025 Written Statements

[The Minister for Veterans and People (Al Carns)]

Between 1952 and 1967, around 22,000 armed forces personnel, as well as scientists and civilians, took part in the UK’s nuclear testing programme in Australia and the Pacific to develop our nuclear deterrent. This nation is deeply grateful for their contribution to the UK’s security.

This Government have reset the relationship with veterans and organisations who represent them so that we can understand their positions and keep them updated on our work. In response to concerns raised with me about some nuclear test veterans’ medical records, I commissioned Ministry of Defence officials to look comprehensively at what information the Department holds.

Today, I want to provide an update on the scope of this exercise. The records exercise is looking at three areas: the policy of blood and urine testing between 1952 and 1967; what information was captured about the blood and urine testing; and if the records did exist, determining what happened to them. The files in scope of the exercise are those in the Ministry of Defence’s archives, as well as the Ministry of Defence’s records now publicly available at the National Archives. If, during the course of this exercise, it is deemed appropriate to alter the scope, we will notify this House.

I understand that many are eager for an update on progress. I want to assure them that this work is being prioritised, and the team have reviewed over 43,000 files, including files from the Merlin database. However, given the vast scale and complexity of the work involved, we are not in a position to confirm when this exercise will conclude. Our focus has been to first review all surviving policy records and instructions related to blood and urine testing, as well as policies relating to the retention of these records. We have started with the policy files to ensure there is an understanding of the policy procedures and instructions given at the time, and officials have been thoroughly identifying and analysing these. Doing this first helps us understand whether policies and instructions were followed, as we then begin the process of looking at nuclear test veterans’ service records. I will update the House when the Ministry of Defence is in a position to share the findings of this exercise.

I will also take this opportunity to provide an update on the release of the Merlin database, which contains over 28,000 records relating to historic technical and scientific documentation on the UK’s nuclear testing programme. The contents of the Merlin database will be transferred to the National Archives as formal public records under the Public Records Act. Records will be held in perpetuity and made available via the public facing online catalogue at TNA called “Discovery”. As the records are digital they will be free to download and there will be no limit on the number that can be downloaded. The records within the database will fall into three broad categories: those that do not hold sensitive data, which will be provided to TNA unredacted; those that are not classified but need to have sensitive personal data redacted under general data protection regulations prior to transfer; and those that will have the necessary GDPR and national security redactions undertaken prior to transfer. The first tranche of records are expected to be transferred to TNA later this summer, once the advisory council on national records and archives has been briefed on the publication.

[HCWS748]