Note that if the lamp is marked for indoor use only, and is not marked with an IP protection rating, this section does not apply.
Guide to IP ratings: https://www.iec.ch/ip-ratings
As a rule of thumb, the following is a guide to required IP levels for lights:
- IPX3 will protect against continuous spray at up to a 60° angle, which is generally considered sufficient in partially enclosed or covered areas.
- IPX4 is more commonly used as a minimum in more exposed spaces.
- If the lights are likely to be cleaned using pressurised jets (e.g. if mounted close to the ground on a garden path or drive), they should be rated at IPX5 or above.
- Any lighting intended for immersion (e.g. pond or pool lighting) up to a depth of 1m must be rated at least IPX7, but always check explicitly with the manufacturer before installing any lighting below the surface of the water.
- Immersion at greater depths will require IPX8, and should again be checked explicitly for precise ingress resistance capabilities before installation.
If the lamp is not to be marked for indoor use, the lamp must be rated to at least IPx4 (where x can be any level of protection). This includes items such as where the cable enters the lamp.
Testing should be as per section 9 of EN 60598 - this over rides EN 60529 for lamps.
IEC 60598 for Luminaires vs. IEC 60529 for Enclosures - comparison of environmental protection requirements: https://kenall.com/Kenall-Files/Product-Files/Literature/Standards-IEC60598vs60529.pdf
PVC insulated cable is not suitable for external use - alternatives such as rubber insulated cable should be used instead.
Attention should be paid to corrosion of metals, either on the outside of the lamp, or on the inside due to corrosion. This involves both the corrosion resistance of the metal itself, and the possibility of corrosion due to two dissimilar metals being in contact (electrolytic or galvanic corrosion).
Plastics such as polystyrene, and materials such as cellulose, should not be used due to their susceptibility to sunlight or a wet environment.
The IP rating should be marked on the lamp, with other installation markings, and also included in the instructions. IP ratings of 20 or less do not need to be marked.
IPx1 to x6 rated lamps shall have a means of letting water out of the lamp, e.g. drain holes.
For IPx1 or higher rated lamps, where rusting of iron/steel components, or corrosion of aluminium components, may make the lamp unsafe, shall be tested to ensure that they are resistant to corrosion.
The requirement to sell lamps with a UK plug attached still applies even though the plug cannot be waterproof, but the lamp instructions must tell the user how to make a connection to the same IP level as the rest of the lamp, e.g. using a waterproof socket and cover, or changing the plug for an alternative waterproof option.