Aurora has created a guide to explain which IP rating lights should go where in a bathroom.
What is IP Zoning
To illustrate IP zoning regulations, the bathroom area is divided up into areas or ‘ZONES’ which are classified using the numbers 0-3. Light fittings are then assigned an ‘IP rating’ which indicates how much protection they provide against ingress of water and other particles. Each zone has a minimum IP requirement that must be met if a fitting is to be installed in this area.
Zone 0 : inside the bath or shower. Any fittings used here must be SELV (max 12V) and have a minimum rating of IPX7 (protected against immersion in water).
Zone 1 : Above the bath or shower to a height of 2.25m. A minimum rating of IPX4 is required*1
Zone 2 : The area stretching to 0.6m outside the bath or shower and above the bath or shower if over 2.25m. An IP rating of at least IPX4 is required *1
Zone 3 : Anywhere outside zones 0,1 & 2. Where water jets are not to be used for cleaning purposes, the general rules of BS7671 apply *1
IP Zoning Notes
1. In Zones 1, 2 & 3, if there is a likelihood of water jets being used for cleaning purposes, a min of IPX5 is required.
2. In Zones 1 and 2, SELV or 240V luminaires may be used (subject to IP rating) 240V luminaires must be protected by a 30mA RCD if installed in Zone 1.
3. There is no requirement for luminaires to be protected against particles or solid objects e.g. IPX4
4. The above information is intended as a guide only. For detailed information, refer to the I.E.E. Wiring regulations (BS 7671: 2001 Section 601).