Any area - designated as such by an
employer and under his control, not being an area designated as a
controlled area -
(a) where it is necessary to keep the conditions of the area under review to determine whether the area should be designated as a controlled area; or
(b) in which any person is likely to receive an effective dose greater than 1mSv a year or an equivalent dose greater than one-tenth of any relevant dose limit referred to in Schedule 4 in respect of an employee aged 18 years or above.
The employer shall ensure that any such designated area is adequately described in local rules and that suitable and sufficient
signs giving warning of the supervised area are displayed, where appropriate, in suitable positions indicating the nature of the radiation sources and the
risks arising from such sources.
