(1) "Fatigue" includes (but is not limited to)—
(a) feeling sleepy; and
(b) feeling physically or mentally tired, weary or drowsy; and
(c) feeling exhausted or lacking energy; and
(d) behaving in a way consistent with paragraph (a),(b) or (c).
(2) The national regulations may contain provisions supplementing, clarifying or providing examples for any of the provisions of sections 223 to 226.