(1) In this section and section 36 -
"Authority" means Irish Aviation Authority;
"determination" means a determination made under subsection (2).
(2) On the expiration of a determination, the Commission shall make a determination specifying the maximum levels of aviation terminal services charges that may be imposed by the Authority.
(3) A determination shall -
(a) be in force for such period of not less than 4 years, and
(b) come into operation on such day, as the Commission specifies.
(4) A determination may -
(a) provide -
(i) for an overall limit on the level of aviation terminal services charges,
(ii) for limits to apply to particular categories of such charges, or
(iii) for a combination of any such limits,
(b) operate to restrict increases in any such charges, or to require reductions in them, whether by reference to any formula or otherwise, or
(c) provide for different limits to apply in relation to different periods of time falling within the period to which the determin