PART X AIR TRAFFIC SERVICES

87 Duty of person in charge to satisfy himself as to competence of controllers
The holder of an approval under article 86 shall not permit any person to act as an air traffic controller or to act as a student air traffic controller in the provision of the service under the approval unless—
(a) such person holds an appropriate licence; and
(b) the holder has satisfied himself that such person is competent to perform his duties.