The
duties imposed by these Regulations shall not extend to -
a)
the master or crew of a sea-going ship or to the employer of such persons, in
relation to the normal ship-board activities of a ship's crew under the direction
of the master; or
b)
the crew of any aircraft or hovercraft which is moving under its own power or
any other person on board any such aircraft or hovercraft who is at work in connection
with its operation.