The Government Says

Guidance: Arrangements for radiation safety of X-ray equipment; PSI 18/2015

Guidance: Arrangements for radiation safety of X-ray equipment; PSI 18/2015
Local copy of PSI_18.2015_AI_13.2015_HS_Arrangements_for_Radiation_of_X-Ray_Security_Equipment.pdf
Local copy of psi-06-2015-pi-03-2015-national-hs-policy-july-2025.pdf

https://www.gov.uk/government/publications/arrangements-for-radiation-safety-of-x-ray-equipment-psi-182015

seen at 16:48, 13 July in Ministry of Justice - Activity on GOV.UK.