Choosing a light fitting for a bathroom, a garden or a plant room comes down to one thing more often than anything else: the IP rating. Get it wrong and you are looking at premature failure, condensation inside the optic, or a genuine safety risk. Get it right and the fitting will still be working a decade later.
This guide has IP ratings explained from first principles. You will find the full IP code chart, what each digit actually means in practice, the ratings required in each bathroom zone under current UK wiring regulations, and how to specify for exterior schemes.
Key points
- An IP rating is a two digit code set by BS EN 60529. The first digit covers solids and dust on a scale of 0 to 6, the second covers water on a scale of 0 to 9.
- Bathroom fittings follow the BS 7671 zones: IPX7 in Zone 0, IPX4 in Zones 1 and 2, and no minimum requirement outside the zones.
- Exterior fittings should be dust tight, so look for a first digit of 6. IP65 suits wall lights, IP67 suits ground recessed uplights and IP68 is essential for anything submerged.
- A higher number is not automatically better. The water scale is not fully cumulative, so an IP67 fitting has not necessarily passed the jet test that an IP66 fitting has.
What Is an IP Rating?
IP stands for Ingress Protection. An IP rating is a two digit code defined by BS EN 60529, the British and European version of the international IEC 60529 standard, and it tells you how well an enclosure resists the entry of solid objects and water.
The code always follows the same format. IP, then a digit for solids, then a digit for water. So IP65 means the fitting is fully protected against dust and can withstand low pressure water jets from any direction.
It is worth being clear about what an IP rating is not. It says nothing about impact resistance, corrosion resistance, UV stability or how the fitting will cope with salt air. Those are separate considerations, and on coastal or high traffic projects they matter just as much.
How to Read an IP Code
Take IP67 as an example.
- IP identifies the code as an Ingress Protection rating
- 6 is the first digit and covers solids, on a scale of 0 to 6
- 7 is the second digit and covers water, on a scale of 0 to 9
The two digits are independent tests. A high first digit does not imply anything about water performance, and the reverse is also true.
What Does the X Mean in IPX4?
You will often see ratings written as IPX4 or IP6X. The X is a placeholder meaning that digit was not tested or is not being declared. IPX4 tells you the fitting resists splashing water but makes no claim at all about dust. IP6X confirms the enclosure is sealed against dust but says nothing about water.
Manufacturers use the X legitimately, but on site it is a gap in the information. If you are specifying for a demanding environment, ask for a fully rated product rather than accepting an X.
IP Rating Chart
First Digit: Protection Against Solids
| Digit | Protection | What it means in practice |
|---|---|---|
| 0 | None | No protection at all |
| 1 | Objects over 50mm | Casual contact with a hand |
| 2 | Objects over 12.5mm | Fingers |
| 3 | Objects over 2.5mm | Tools and thick wires |
| 4 | Objects over 1mm | Screws, most wires |
| 5 | Dust protected | Dust may enter but not in a quantity that affects operation |
| 6 | Dust tight | No dust ingress whatsoever |
Second Digit: Protection Against Water
| Digit | Protection | Test condition |
|---|---|---|
| 0 | None | No protection |
| 1 | Dripping water | Vertical drips |
| 2 | Dripping water when tilted | Drips at up to 15 degrees |
| 3 | Spraying water | Spray at up to 60 degrees from vertical |
| 4 | Splashing water | Splashes from any direction |
| 5 | Water jets | 6.3mm nozzle from any direction |
| 6 | Powerful water jets | 12.5mm nozzle, heavy seas |
| 7 | Temporary immersion | 1m depth for 30 minutes |
| 8 | Continuous immersion | Depth and duration specified by the manufacturer |
| 9 | High pressure hot jets | Close range steam cleaning, often written IP69K |
One point that catches people out: the water scale is not perfectly cumulative. An IP67 fitting has passed an immersion test but has not necessarily passed the jet test at level 6. If a fixture will face both hose down cleaning and standing water, look for a dual declaration such as IP66 and IP68.
Common IP Ratings Explained
These are the ratings that come up most often on residential and commercial lighting projects.
| Rating | Suitable for |
|---|---|
| IP20 | Standard interior fittings in dry rooms |
| IP23 | Sheltered exterior positions such as a covered porch |
| IP44 | Bathroom zones 1 and 2, sheltered garden lighting |
| IP54 | Utility rooms, garages, workshops |
| IP65 | General exterior wall lights, facade washing, coastal soffits |
| IP66 | Exposed exterior positions, ground recessed uplights |
| IP67 | Locations where water pools, driveways, planted beds |
| IP68 | Pond and swimming pool lighting, permanently submerged fittings |
| IP69K | Food production, car washes, anywhere steam cleaned at pressure |
IP Ratings for Bathroom Lighting
UK bathroom lighting is governed by BS 7671, the IET Wiring Regulations. The room is divided into zones measured from the bath or shower, and each zone carries a minimum IP requirement.
Zone 0
The interior of the bath tub or shower tray itself. Any fitting here must be rated IPX7 as a minimum and must be SELV, limited to 12 volts.
Zone 1
The area directly above the bath or shower, up to 2.25m above finished floor level, or to the height of the shower head if that sits higher. The minimum here is IPX4. If the space will be cleaned with a water jet, step up to IPX5.
Zone 2
A 0.6m band extending outwards from the edge of Zone 1, and the same 0.6m band around any wash basin. The minimum is again IPX4, rising to IPX5 where water jets are used. Window recesses and openings within this area count as Zone 2.
Outside the Zones
Beyond Zone 2 there is no specific IP requirement, so a standard IP20 fitting is permitted. That said, bathrooms are humid rooms and a sealed fitting will simply last longer, so IP44 across the whole ceiling is a sensible default rather than a strict rule.
A note on Zone 3: older guidance refers to a Zone 3 extending 2.4m beyond Zone 2. That zone was removed from BS 7671 at the 17th Edition and no longer exists in the current regulations. If you are reading a specification that still cites it, the document is out of date.
Bear in mind that electrical work in a bathroom is notifiable under Part P of the Building Regulations in England and Wales. It should be carried out or certified by a competent person.
IP Ratings for Outdoor Lighting
Exterior fittings face driving rain, frost, dust, UV and thermal cycling. As a working baseline, aim for a first digit of 6 so the enclosure is fully dust tight, then choose the water digit according to position.
Wall lights and facade lighting. IP65 is usually sufficient on a vertical surface where water runs off. Coastal sites are the exception, where marine grade 316 stainless steel or powder coated aluminium matters as much as the IP code.
Ground recessed uplights. IP67 as a minimum. Water pools around recessed fittings whenever drainage is imperfect, which is most of the time. IP68 is better still if the surrounding ground is planted or prone to saturation.
Spike lights and bollards. IP65 to IP66 covers rainfall and irrigation spray.
Pond and pool lighting. IP68 only, and check the declared depth and duration. IP68 is the one rating where the manufacturer sets the test conditions, so two IP68 products are not necessarily equivalent. We have seen IP68 fittings in Italy that have run continuously underwater for more than ten years, and we have seen others fail within a season. The declaration is what separates them.
Step and deck lights. IP67, since these sit at the level where water collects and where they may be jet washed.
The most common exterior failure we are called out to is not water passing through a seal. It is condensation forming inside the fitting because a gland was left loose, a cable was cut short, or the glass cracked in a hard frost. The IP rating is only as good as the installation.
IP Ratings and IK Ratings
IP covers ingress. IK covers impact, and it is measured on a scale from IK00 to IK10 based on the energy in joules that the enclosure can absorb.
The two ratings are often needed together. A bollard on a car park perimeter, a wall light in a school corridor or a ground light in a public square all need mechanical strength as well as a sealed body. IK08 and above is the usual specification for public realm work, and IK10 for anywhere genuinely exposed to vandalism.
How to Choose the Right IP Rating
Work through four questions.
- Where exactly is the fitting? Not the room, the precise position. A ceiling light 2m from a shower and one directly above it are different problems.
- How will it be cleaned? Jet washing pushes the requirement up to a water digit of 5 or 6 regardless of weather exposure.
- Can water sit against it? If yes, you need 7 or 8, not 6.
- Can it be struck? If yes, check the IK rating alongside the IP rating.
Overspecifying carries a cost in price and often in fitting size, so there is no benefit in putting IP68 in a hallway. Underspecifying costs far more, because the fitting will need replacing and the labour to reach a recessed or buried fixture is rarely trivial.
Frequently Asked Questions
What does IP mean in IP rating? IP stands for Ingress Protection. It is a standardised code defined by BS EN 60529 that describes how well an enclosure resists solid objects and water.
Is IP65 waterproof? IP65 is water resistant rather than waterproof. It withstands low pressure jets from any direction but is not rated for immersion. For submersion you need IP67 or IP68.
What is the difference between IP44 and IP65? IP44 protects against solid objects above 1mm and splashing water. IP65 is fully dust tight and withstands water jets. IP44 suits sheltered positions, IP65 suits open exterior positions.
What IP rating do I need for a bathroom light? IPX7 in Zone 0, IPX4 in Zones 1 and 2, and no minimum outside the zones. IP44 throughout is a practical default for a domestic bathroom.
What is the highest IP rating? IP69K, which covers close range high pressure hot water jets. For lighting, IP68 is the highest rating in general use.
Does a higher IP rating always mean better? No. The two digits test different things, and the water scale is not fully cumulative. An IP67 fitting has not necessarily passed the jet test that an IP66 fitting has passed.
Specifying With Confidence
If you are working through a scheme and are unsure which rating a particular position calls for, our technical team can review the layout with you. We supply fittings across the full IP range and design lighting schemes where the specification is right from the outset rather than corrected after installation.
