IP Ratings and Bathroom Zones

All light fittings have an IP rating, whether they are elaborate chandeliers, wall sconces, garden lights or LED downlights. You might well ask: what is an IP rating?

The IP rating defines how effectively electrical enclosures are sealed against ingress of solid objects and water. It is expressed with two digits, each of which corresponds to a particular level of ingress protection (IP).

The second digit in the IP rating is the one that particularly concerns downlights, because it dictates where they can and cannot be installed in a building. Below are some examples.

  • IPX0: light fixture offers no protection against water and therefore cannot be exposed to moisture or liquids.
  • IPX1/IPX2: minimal protection against water and would still be unsuitable for installation in areas directly exposed to water or moisture (these ratings are relatively rare).
  • IPX3: basic protection against water, withstanding spray from a 60° angle (irrelevant with downlights). This is usually the minimum requirement for outdoor lights.
  • IPX4: this IP rating is useful for downlights, since it means the fitting can withstand splashing from any angle. However, a higher rating is advisable for resistance to powerful water jets.
  • IPX5/IPX6: this level of protection is adequate inside shower cubicles. A lower IP rating may be enough in a ceiling above a shower unit.
  • IPX7/IPX8: not applicable to downlights unless installed abnormally; this level of protection allows a light fitting to be submerged in water and indicates suitability inside a bath or shower tray.

Bathroom Zones

The IP rating is of special relevance when installing downlights or other fixtures in bathrooms and washrooms. Bathrooms are divided into zones in accordance with IEE Wiring Regulations, which also inform building regulations. Each zone demands a minimum IP rating in light fixtures. The bathroom zones are as follows:

  • Zone 0: Within a bath tub or shower tray = IPX7+ and 12V SELV
  • Zone 1: directly above bath and inside shower cubicle = IPX4+
  • Zone 2: immediate area around bath or shower = IPX4+
  • Outside Zones (previously Zone 3): no minimum required unless for cleaning purposes