Access status of ES/DEFE files

Request

1. The date on which these documents were requested from the TNA by the Ministry of Defence.
2. The date on which they became unavailable to the public, if different.
3. The reason given for the request.

The documents are:

• DEFE 16/220 – Operation Mosaic: trials, health physics
• DEFE 16/221 – Operation Mosaic; trials, health physics
• DEFE 16/319 – Health physics reports Maralinga
• DEFE 16/927 – Record of meetings to discuss requirement for serving contaminated Canberra aircraft and specification for health physics control area at Edinburgh Field
• DEFE 16/160 – Operation Antler: health physics services
• ES 1/1285 – Maralinga health physics reports
• ES 1/1286 – Maralinga health physics reports
• ES 1/1287 – Maralinga health physics reports
• ES 1/1288 – Maralinga health physics reports
• ES 5/250 – Health physics services Operation Antler
• DEFE 16/491 – Maralinga range: health physics management
• DEFE 16/492 – Maralinga range: health physics management

Outcome

Information provided.

Response

1. The date on which these documents were requested from the TNA by the Ministry of Defence

2. The date on which they became unavailable to the public, if different.

For questions 1 and 2, please see below.

• DEFE 16/220 – Operation Mosaic: trials, health physics
  Request form dated 08/05/2025, request emailed to TNA 08/05/2025. Became unavailable: 14/05/2025.
• DEFE 16/221 – Operation Mosaic; trials, health physics
  Request form dated 08/05/2025, request emailed to TNA 08/05/2025. Became unavailable: 14/05/2025.
• DEFE 16/319 – Health physics reports Maralinga
  Request form dated 08/05/2025, request emailed to TNA 08/05/2025. Became unavailable: 14/05/2025.
• DEFE 16/927 – Record of meetings to discuss requirement for serving contaminated Canberra aircraft and specification for health physics control area at Edinburgh Field
  Request form dated 08/05/2025, request emailed to TNA 08/05/2025. Became unavailable: 14/05/2025.
• DEFE 16/160 – Operation Antler: health physics services
  Request form dated 08/05/2025, request emailed to TNA 08/05/2025. Became unavailable: 14/05/2025.
• ES 1/1285 – Maralinga health physics reports
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025.
• ES 1/1286 – Maralinga health physics reports
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025.
• ES 1/1287 – Maralinga health physics reports
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025.
• ES 1/1288 – Maralinga health physics reports
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025.
• ES 5/250 – Health physics services Operation Antler
  Request form dated 29/11/2024, request emailed to TNA 03/12/2024. Became unavailable: 13/01/2025.
• DEFE 16/491 – Maralinga range: health physics management
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025
• DEFE 16/492 – Maralinga range: health physics management
  Request form dated 07/01/2025, request emailed to TNA 13/01/2025. Became unavailable: 16/01/2025.

Please note that the date for when the record became unavailable is the date the record has been ordered on our ordering system. Once an order request is received, the record is prevented from being ordered and the public terminals will show the record as being ‘in use’.

3. The reason given for the request.

Section 4 (6) of the Public Records Act 1958 enables government departments to recall documents of their own origin for the purposes of display or exhibition, publication, and to conduct official business and review. Transferring government departments do not need to give a reason why they are requesting the documents for recall.

The ES records all relate to the United Kingdom’s Nuclear Weapons programme, which are currently undergoing review by the Ministry of Defence. While these reviews are ongoing, a number of the records have been withdrawn from general access until the assessment is complete. Further information relating to the ongoing review of these records can be found here: Review of nuclear archive records – GOV.UK

The records in the DEFE series that were ordered by the MoD do not relate to this review. The MoD did not provide a reason for the recall of those records in the DEFE series.