(1)For the purposes of this Part—
(a)" work" means work as an employee or as a self-employed person;
(b)an employee is at work throughout the time when he is in the course of his employment, but not otherwise ; and
(c)a self-employed person is at work throughout such time as he devotes to work as a self-employed person;
and, subject to the following subsection, the expressions " work " and " at work", in whatever context, shall be construed accordingly.
(2)Regulations made under this subsection may—
(a)extend the meaning of " work " and " at work " for the purposes of this Part; and
(b)in that connection provide for any of the relevant statutory provisions to have effect subject to such adaptations as may be specified in the regulations.
(3)The power to make regulations under subsection (2) above shall be exercisable—
(a)in relation to activities not relating exclusively to agricultural operations, by the Secretary of State;
(b)in relation to activities relating exclusively to the relevant agricultural purposes, by the appropriate agriculture authority.
(4)Regulations under subsection (2) above in relation to activities falling within subsection (3)(b) above may be either regulations applying to Great Britain and made by the Minister of Agriculture, Fisheries and Food and the Secretary of State acting jointly, or regulations applying to England and Wales only and made by the said Minister, or regulations applying to Scotland only and made by the Secretary of State; and in subsection (3)(b) above " the appropriate agriculture authority " shall be construed accordingly.