The bathroom: lighting and the safety zones

A bathroom is a wet room, and that makes it special from an electrical point of view. Moisture, splashing water and sometimes immersion mean that current finds a path to your body far more easily than in a dry room. Stand with wet feet on a wet floor and your resistance is low, so a fault that would be harmless elsewhere can end badly here. For that reason NEN 1010, the standard for safe electrics in and around the home, sets extra requirements for everything you connect in a bathroom.

Those requirements are not the same everywhere in the room. Just above the bath the risk is greater than by the door on the far side. That is why the standard works with zones: imaginary areas around the bath and shower, each with its own degree of strictness. The closer to the water, the higher the requirements for the protection of a fitting, and the lower the voltage that may safely run there.

The idea behind it is simple: in the place where water and person are closest, as little energy as possible should be available and every device must be fully protected against water. Moving outwards, away from the bath, a little more is gradually allowed. That way you keep the bathroom usable without losing sight of safety.

Zone 0 is the area inside the bath or shower tray itself: where the water sits. This is the strictest zone. Only devices expressly made for this spot are allowed here; they must be waterproof to immersion (IPX7) and run on safe low voltage, usually 12 volts SELV via an isolating transformer outside the bathroom.

Zone 1 is the space directly above zone 0, up to a height of 225 cm above the floor. Think of the wall above the bath or shower, where a recessed spotlight or a suitable water heater can be fitted, for example. Here a minimum of IPX4 applies, so protection against splashing water from all directions. Ordinary sockets are not allowed here.

Zone 2 runs 60 cm horizontally on from the edge of zone 1, also up to 225 cm high. This is the area directly beside the bath or shower, where a wall fitting by the mirror might sit, for example. Here too IPX4 is the minimum. Sockets are not permitted in this zone, with the exception of a shaver socket with a built-in isolating transformer.

Everything beyond these zones counts as normal, provided it stays reasonably clear of splashing water. There, ordinary sockets and switches are allowed, along with fittings without a special IP requirement. However, for the whole bathroom the circuit must be protected by a 30 milliamp RCD, whichever zone you are in.

IP stands for Ingress Protection, the degree to which a device is protected against the ingress of dust and water. After the letters come two digits: the first is about solid particles and dust, the second about water. For bathroom fittings it is mainly that second digit that matters, which is why you often see a notation like IPX4, where the X means the dust digit is not specified here.

IPX4 means protection against splashing water from all directions: a fitting that can handle this is unaffected if water splashes against it. That is the minimum requirement in zones 1 and 2. IPX5 goes a step further and withstands water jets, handy if you clean the shower or room with a jet. IPX7, finally, means a device withstands temporary immersion, and that is exactly why that requirement applies to zone 0, inside the bath.

A higher second digit is therefore stricter, and the zone determines which minimum you need. If you buy a spotlight or wall light for the bathroom, always check the IP rating on the packaging and compare it with the zone where it will hang. An ordinary lamp from the living room, without an IP marking, does not belong within the wet zones.

On paper the zones look manageable, but in practice the safety is in the details. The right IP rating per zone, a 30 milliamp RCD that actually switches off in time, good earthing and the question of whether your existing circuit safely feeds the bathroom: together that makes the difference. A fault is invisible from the outside, until it goes wrong in the worst possible place.

Work on the fixed installation in a wet room therefore belongs with a certified professional who works to NEN 1010. That is not only safer, it is also important for your insurance: if something goes wrong with electrics that were not installed to the standard, cover can come into question. A certified electrician tests the installation afterwards and hands it over demonstrably safe.

Not sure whether your bathroom is still up to standard, for instance in an older home or after a past renovation? Have it checked at your leisure. We assess the zones, the IP ratings and the protection, and tell you honestly what is needed and what is simply fine.