[11AWorking in United Kingdom watersU.K.
(1)An “offshore worker” is a person who arrives in United Kingdom waters—
(a)for the purpose of undertaking work in those waters, and
(b)without first entering the United Kingdom (see, in particular, section 11(1)).
But see subsection (6).
(2)An offshore worker arrives in the United Kingdom for the purposes of this Act when they arrive in United Kingdom waters as mentioned in subsection (1)(a).
(3)An offshore worker enters the United Kingdom for the purposes of this Act when they commence working in United Kingdom waters.
(4)Any reference in, or in a provision made under, the Immigration Acts to a person arriving in or entering the United Kingdom, however expressed, is to be read as including a reference to an offshore worker arriving in or entering the United Kingdom as provided for in subsection (2) or (3).
(5)References in this section to work, or to a person working, are to be read in accordance with section 24B(10).
(6)A person is not an offshore worker if they arrive in United Kingdom waters while working as a member of the crew of a ship that is—
(a)exercising the right of innocent passage through the territorial sea or the right of transit passage through straits used for international navigation, or
(b)passing through United Kingdom waters from non-UK waters to a place in the United Kingdom or vice versa.
(7)For the purposes of any provision of, or made under, the Immigration Acts, a person working in United Kingdom waters who, in connection with that work, temporarily enters non-UK waters is not to be treated by virtue of doing so as leaving, or being outside, the United Kingdom.
(8)In this section—
“non-UK waters” means the sea beyond the seaward limits of the territorial sea;
“right of innocent passage”, “right of transit passage” and “straits used for international navigation” are to be read in accordance with the United Nations Convention on the Law of the Sea 1982 (Cmnd 8941) and any modifications of that Convention agreed after the passing of the Nationality and Borders Act 2022 that have entered into force in relation to the United Kingdom;
“the territorial sea” means the territorial sea adjacent to the United Kingdom;
“United Kingdom waters” means the sea and other waters within the seaward limits of the territorial sea.]