# The Nuclear Safeguards (Notification) Regulations 2004, Paragraph 5.1.1: Rotating components


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(b) Rotor tubes:
Especially designed or prepared thin-walled cylinders with thickness of 12 mm (0.5 in) or less, a diameter of between 75 mm (3 in) and 400 mm (16 in), and manufactured from one or more of the high strength to density ratio materials described in the EXPLANATORY NOTE to this Section.
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Source: https://www.legislation.gov.uk/uksi/2004/1255/schedule/part/II/paragraph/5n3 (the official version)
Page: https://openlegislation.uk/nuclear-safeguards-notification-regulations-2004/schedule/part-II/paragraph-5n3
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.