ANNEX VIIU.K.FREQUENCY OF EXAMINATIONS
The minimum frequency of the periodic checks shall be as follows:
(a)
linguistic knowledge (only for non-native speakers): every three years or after any absence of more than one year;
(b)
infrastructure knowledge (including route and operation rules knowledge): every three years or after any absence of more than one year on the relevant route;
(c)
knowledge of rolling stock: every three years.