IP65 vs IP66 vs IP67: What Outdoor Lighting Buyers Actually Need to Know
Sep 09, 2026
Every outdoor lighting specification sheet carries an IP code, and most project buyers read it as a score: IP67 beats IP66, IP66 beats IP65, done. That reading feels safe, and it is wrong. The second digit of an IP code describes which water threat a luminaire was tested against, not its overall level of protection.
This article breaks down what IP65, IP66 and IP67 actually measure under IEC 60529, why the three numbers are not rungs on one ladder, and how to match each rating to the environments and mounting positions you run into on coastal, desert and landscape projects.
Why the Second Digit Is Not a Ranking
An IP code is defined by IEC 60529 and carries two digits. The first digit, from 0 to 6, rates protection against solids and dust. The second digit, from 0 to 9, rates protection against water. For outdoor luminaires the first digit is usually 6, meaning dust-tight. Everything interesting happens in the second digit.
Here is the part that catches buyers: the water tests split into two different families. Digits 5 and 6 cover jets, where a nozzle directs pressurized water at the enclosure. Digits 7 and 8 cover immersion, where the luminaire sits underwater under static pressure. These tests use different equipment, acceptance criteria and loading conditions. The standard does not require a product to pass the IPX6 test before undergoing the IPX7 test, so IP67 is not "IP65 plus more". It is the result of a different test for a different type of water exposure.
What Each Rating Actually Tests
| Code | Second digit test | Test conditions (IEC 60529) | Typical exposure |
|---|---|---|---|
| IP65 | Low-pressure jets | 6.3 mm nozzle, about 12.5 L/min, from any direction | Rain, wind-driven spray, hose washing |
| IP66 | Powerful jets | 12.5 mm nozzle, about 100 L/min, from any direction | Heavy washdown, driving sea spray |
| IP67 | Temporary immersion | 1 m depth, 30 minutes | Standing water, brief flooding |
IP65: Low-Pressure Jets
IP65 is the workhorse rating for outdoor luminaires. The test uses a 6.3 mm nozzle to spray the enclosure from every direction, providing a reasonable simulation of wind-driven rain and routine hose cleaning. Most above-ground fixtures on a project, from bollards to wall packs, live comfortably at IP65.
IP66: Powerful Jets
The IP66 test uses a larger 12.5 mm nozzle with a flow rate of roughly 100 L/min. That is closer to a pressure-washer pass than to weather. The rating matters where luminaires get aggressively cleaned: marine and harbor installations, food and beverage plants, transport hubs with scheduled washdown programs. It also buys margin in locations that take the full force of storm-driven spray.
IP67: Temporary Immersion
IP67 ignores jets and tests something else: the luminaire survives submersion at 1 m for 30 minutes with no harmful ingress. This is the rating for fixtures that spend part of their life underwater. In-ground walkover lights sit in soil that saturates after heavy rain. Garden uplights near pond edges get flooded. Grade-level fixtures in plazas stand in puddles for days. None of those situations involves a jet; all involve standing water, which is the exposure covered by IP67.
Why IP67 Is Not an Upgrade of IP65
The two tests load the seals in different ways. Immersion applies even, static pressure across the whole housing. A jet concentrates force on a small area, enough to deform a gasket locally or drive water through a seam that would hold perfectly well underwater. A luminaire sealed for immersion may leak under a jet, and a jet-rated luminaire may leak after an hour in a puddle. The numbers do not stack because the tests do not nest.
There is also a design difference. Jet-rated fixtures often use gasketed enclosures that can drain and dry after washdown. Immersion-rated fixtures are built as sealed enclosures, often with membranes or vents to manage the pressure changes that come with daily heating and cooling cycles. Using an immersion-focused design for jet exposure, or a jet-rated design in standing water, exposes each enclosure to conditions it may not be designed to handle.
The practical takeaway: read the second digit as an answer to one question. "Will this fixture be hosed?" points to 5 or 6. "Will this fixture stand in water?" points to 7 or 8. If both are true, ask the supplier for evidence of both tests, declared as a dual rating.
Matching Ratings to Real Environments
Coastal Projects
On coastal sites, the main water exposures are wind-driven spray and pressure washing during maintenance. Both are jet-type threats, so IP65 is the floor and IP66 is worth specifying on exposed promenades, deck-level positions and anywhere cleaning crews work with hoses. Salt adds a second axis: an IP number says nothing about corrosion resistance, so pair the rating with marine-grade materials such as die-cast aluminum with a sound coating system, and 316 stainless hardware where available. A dust-tight housing that pits through in two seasons protects nobody.
Desert Projects
Desert sites are primarily a dust-control problem, so specify a first digit of 6, dust-tight, for anything exposed to sandstorms and fine grit. Water is rarer but arrives in the worst possible form, as flash flooding across graded ground and in drainage paths. Fixtures mounted at or near grade, especially any in-ground unit, should carry IP67 for exactly that reason. Above-grade luminaires at IP65 handle the occasional violent rain event. One more desert note: large day-to-night temperature swings repeatedly stress the gaskets. Ask how the enclosure manages thermal breathing, because a rating established under laboratory conditions does not guarantee the same sealing performance after two years of thermal cycling.
Gardens and Landscapes
A landscape project has more water in motion than most buyers expect. Irrigation and sprinkler systems can direct water at fixtures every night, including units mounted only 300 mm above grade. That argues for IP65 as the baseline for path and area lighting. Saturated soil is the next concern. After several days of irrigation or a heavy storm, an in-ground recess can fill with water, so walkover fixtures typically require IP67. Match the rating to the threat at each mounting height rather than picking one number for the whole site.
Ratings by Mounting Location
Bollards and Path Lights
Bollards stand in open ground, take rain and irrigation spray from all sides, and rarely stand in water. IP65 is the appropriate rating, and a typical specification looks like our bollard lights range: a 12 W die-cast aluminum unit at IP65, built as a drainable above-grade enclosure. Paying for an immersion rating here adds cost without addressing a condition the fixture is unlikely to encounter.
Floodlights and Area Lights
Floodlights mount high, face the sky and take the full force of wind-driven rain. Jet protection is what matters, which is why the 50 W anti-glare units in our flood lights range are rated IP65 for this application. At mounting heights above 4 m, immersion is not a realistic exposure, so an IP67 rating on a pole-mounted floodlight may provide no practical benefit.
In-Ground and Buried Fixtures
Anything set into soil, paving or decking lives with saturated ground. Water sits against the housing for hours or days, so temporary immersion is the governing test, and IP67 is the right answer. One example from our in-ground lights range is a 9 W aluminum walkover light, 114 mm high and rated IP67 for temporary immersion. Check the details that support reliable IP67 performance: a sealed cable gland, proper drainage of the housing cavity below the lens, and a load rating suited to the expected traffic.
Wall and Facade Lights
Wall-mounted decorative fixtures usually sit in sheltered facade positions: under soffits, behind balconies, on walls protected by roof overhangs. In those positions the exposure is splash and dripping water, not jets or immersion, which is why the 15 W round decorative units in our outdoor wall lights range are correctly rated IP54. Reading IP54 as "worse than IP65" misses the point. It is a rating matched to an installation position. Where a facade is fully exposed to driving coastal rain, step up to IP65, but do not specify higher ratings across the board. A tightly sealed, unvented enclosure may not be appropriate for every mounting position.
IP67 vs IP68: When Immersion Goes Further
IP67 certifies temporary immersion: 1 m depth for 30 minutes. IP68 covers continuous immersion, and here the standard is open-ended: the depth and duration are declared by the supplier rather than fixed by IEC 60529. An IP68 claim without a stated depth and duration is incomplete, so ask the supplier to provide the actual test conditions.
Which projects should move from IP67 to IP68? Consider IP68 when the fixture will operate continuously in water or at the waterline: for example, in permanently flooded areas, at pool edges where the housing sits at or below water level, in low points that remain submerged for extended periods, or in water features. If immersion is an accident the fixture must survive, IP67 is the honest rating. If immersion is the operating condition, specify IP68 and demand the declared depth and duration in writing.
One final point: IP68 covers immersion, not water jets. A submersible unit has not automatically passed a hose test, for the same reason an IP67 unit has not automatically passed an IP65 test. Where washdown and submersion both apply, the supplier should declare both.
How to Verify the Rating Before You Sign
An IP code on a website is only a claim. Verify it before including it in your project specification:
- Ask for the test report. A report against IEC 60529 from a laboratory, naming the luminaire, is the baseline. A screenshot of the code is not evidence.
- Check which digit tests were actually performed. The report shows the tested characteristics. If you need jet and immersion performance, confirm both appear, or ask for a dual declaration.
- Confirm the test orientation. Enclosures are tested in their in-service mounting position. A housing rated upright may not hold the same code tilted or inverted.
- Read the warranty's water language. Find out whether water ingress is covered, and under which installation conditions. The gap between the IP claim and the warranty terms is where projects get stuck.
- Inspect the sealing design. Cable glands, gasket material, vent membranes and drain paths tell you whether the rating was engineered or printed. A quick review of the enclosure cross-section can tell you more than the IP number alone.
- The IP code is a ruler, not a prize. Once you know what each digit measures, the right question stops being "which number is highest" and becomes "which test does this fixture need to survive". Buyers who ask that question write specifications that hold up in the field, and suppliers who answer it clearly earn the next order.
