Zone 0 is inside the bath or shower itself. Any fitting used in this zone must be low voltage (max 12v) and be at least IP67 rated which is immersion proof.
Zone 1 is the area above the bath to a height of 2.25m from the floor. In this zone a minimum rating of IP44 is required.
Zone 2 is an area stretching 0.6m outside the perimeter of the bath and to a height or 2.25m from the floor. In this zone an IP rating of IP44 is required.
In accordance with advice from the Lighting Industry Association, the location above Zone 1 (over the bath or shower) up to a ceiling height of 3m continues to be classified as Zone 2.
If at all in doubt it is always our advice to ask an electrician.