Materials & compliance · 7 min read
IPX5, IPX6 and IPX7: choosing a rating
The numbers look like a ladder. They are not — each is its own test, and the difference matters for both marketing copy and warranty.
Reading an IP code
The IEC 60529 code has two digits. The first covers protection against solid particles; where it has not been tested it is written as X. The second covers water. IPX5 therefore means "entry protection not rated against solids, water protected to level 5" — which is why X appears so often in this category.
The code describes the enclosure, not the electronics inside it, and it says nothing about how long a rating holds after wear. [International Electrotechnical Commission, 2013] is the standard itself: the two digits are defined there and nowhere else.
What each rating requires
| Rating | Test condition | Practical meaning |
|---|---|---|
| IPX4 | Water splashed from any direction, limited ingress permitted | Survives cleaning under a tap |
| IPX5 | Water jet from a 6.3 mm nozzle, water volume defined, from any direction | Washable under running water |
| IPX6 | Powerful jet from a 12.5 mm nozzle, higher volume | Robust against heavier exposure |
| IPX7 | Immersion to a stated depth, commonly 1 m, for a stated duration | Survives accidental immersion |
Choosing for your market
Rating choice is a commercial decision more than an engineering one. Higher ratings cost more to engineer and more to verify per unit; the cheapest rating that supports your claims honestly is usually the right one.
- Bath-use positioning. The marketing proposition implies immersion, so the rating has to support it.
- Cleaning claims. "Washable" is a claim about a jet, which points at IPX5 or above.
- Retail channel. Some retailers have category-wide requirements that exceed what consumers would ask for.
- Return economics. Node seals and charging contacts are where field failures concentrate; the rating should reflect the way customers actually use the product.
Water resistance across the range spans several ratings depending on model, which is why the full range page states the rating per model rather than once for the catalogue. Each one is verified per batch — see the four-stage quality system for where that test sits.
Testing honestly
Two things distinguish a rating from a claim. First, whether the test was performed on production units or only on a qualification sample; second, whether the batch records show it. Per-batch water-resistance reports are part of what ships with a Slow Duo order, listed in the per-order compliance file, so the units cleared are the units whose test report you hold.
References
- International Electrotechnical Commission (2013). Degrees of protection provided by enclosures (IP Code), IEC 60529, Edition 2.2. Geneva: IEC.
- Juran, J. M. & Godfrey, A. B. (1999). Juran's Quality Handbook, 5th ed. New York: McGraw-Hill.
- Montgomery, D. C. (2020). Introduction to Statistical Quality Control, 8th ed. Hoboken, NJ: Wiley.
Questions on this guide
Does IPX7 include IPX6?
Not automatically. Each level specifies its own test conditions, so claim only the ratings the product was actually tested against.
Can an IP-rated product be used underwater indefinitely?
IPX7 covers temporary immersion to a defined depth and duration. Anything beyond that condition is outside what the rating promises.
Why is the solid digit often X?
Because it has not been tested to that part of the standard, and claiming untested digits is the very thing the code exists to prevent.
Is a higher IP number always better?
No. Submersible does not imply jet-safe, and the number that matters is the one matching how the product will actually be used and cleaned. A buyer selling a shower product and a buyer selling a bath product need different codes.
How long does a rating hold?
The rating describes a sealed unit at the time of test. Seals age, a dropped housing can break a seal, and a charging port cover is a wear item. It is a design test, not a lifetime warranty.
Does a colour change require the rating to be re-tested?
It can. A new colour is a new compound batch: the seal geometry is unchanged, but moulding shrinkage may not be. We re-run the ingress test on the first production batch of any new colourway rather than assume the rating carries over, because that batch is where a leak would show.
What does IPX5 not cover?
Immersion, and steam. IPX5 is a jet test — water projected at the enclosure from any direction at a defined volume and pressure — so it covers rinsing under a tap and bathroom storage, and says nothing about a basin or a shower at close range. If a customer might submerge the unit, specify IPX7.
Still open: what IPX5 does not cover — or filter the range by ingress rating.