IPX5, IPX6 and IPX7: choosing a rating

What does IPX7 mean, and is "waterproof" the same claim?

IPX7 is a specific test result, not a marketing word. According to the Wikipedia entry IP Code, the second digit describes a defined immersion condition under IEC 60529, and it is not interchangeable with the jet-spray condition of IPX5 — a product can pass one and not the other. Ask for the test record, the duration and the depth, and check whether the claim covers the charging port as well as the body. The specification fields show where that record is filed per model.

How do you read an IP code on a product page?

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, and why the second digit is the only one a buyer of this product usually has to argue about.

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, which is why a supplier quoting "IP67-grade" without a test report is quoting a shape rather than a result.

What does each IPX rating actually require in numbers?

The levels are separated by nozzle diameter, flow rate, distance and duration — four numbers that decide whether a unit passes. They are worth knowing because they are checkable: a factory that cannot state the nozzle, the flow and the duration for the rating on its own label has not run the test, or has run something else and named it afterwards.

Two of those columns do different work. The middle one is what the lab does; the right-hand one is what the buyer believes they bought. Most warranty disputes in this category live in the gap between them — a customer reads "IPX6" as "submersible" because 6 is higher than 5, runs a bath, and the unit fails a condition it was never tested against.

IPX6 vs IPX7 — does the higher number include the lower?

This is the single most useful thing to understand about the code, and the thing retail copy gets wrong most often. IPX6 is not "more waterproof than IPX5" in the sense of containing it. It is a different test with a different nozzle: 12.5 mm at 100 litres a minute instead of 6.3 mm at 12.5. A housing optimised for a heavy jet is not thereby optimised for a long low-pressure soak, and a housing that survives both may still fail a splash test aimed at a seam the jet never reached.

• Claim only what was tested. A unit tested to IPX7 and not to IPX6 may be described as IPX7. Describing it as IPX5/IPX6/IPX7 because the number is higher is a claim about a test nobody ran.
• Specify the pair you need. Bath positioning implies immersion (IPX7); shower and cleaning claims imply a jet (IPX5 or IPX6). Where both apply, both belong in the specification, listed separately.
• Ask for the condition, not the level. "IPX7, 1 m, 30 minutes" is a specification. "IPX7" alone is a label, and the depth is the part that decides whether a basin counts.

What does a single IPX number mean on its own?

A quotation that says only "IPX5" or only "IPX6" is making a narrower claim than it looks. The X removes any dust statement, so what remains is one water test at one severity, and the number tells you which severity. IPX5 on its own means a 6.3 mm nozzle at 12.5 l/min for three minutes from three metres — a jet a buyer would use to rinse a unit under a tap. IPX6 on its own means a 12.5 mm nozzle at 100 l/min for the same three minutes, which is a hose, not a tap. Neither number says anything about dust, drops, or immersion, and neither can be extended by reading it as a point on a scale.

This matters most in a tender, because "IPX5" and "IP55" can both be defended and only one of them answers a dust question. If the market you sell into asks for dust protection — a beach product, a workshop tool, anything stored in a bag — the single water number is the wrong document to send, however high it is. The [International Electrotechnical Commission, 2013] set the two digits as independent statements for exactly this reason.

IPX5 vs IP55 — what the X is not telling you

Buyers reach this page with a comparison the code does not support. "IPX5 vs IP55" reads like two grades on one ladder, and the longer string looks stronger. They are not the same kind of statement. The X in IPX5 is not a poor score for dust — it is the absence of a claim: the dust test was not run, so no result is written there. IP55 puts dust *protected* in the first digit and exactly the same water jet as IPX5 in the second. IP55 is therefore IPX5 plus a dust claim, and never a water upgrade.

The reverse error costs more. An IP55 listing has said nothing about immersion, so an IP55 unit pushed into a basin is outside the test it passed. And IPX5 says nothing about dust, which for a silicone body that lives in a bathroom is rarely the constraint — that is why the X is common in this category, and why an IP55 comparison usually leads away from the question the buyer meant to ask.

The rule that survives a purchase order: write both digits when both were tested (IP55, IP67), and X when the dust test was not run (IPX5, IPX7). A supplier that upgrades its own label from IPX5 to IP55 without a dust report has changed the paperwork, not the product. Ask which laboratory ran the first-digit test, to which clause, and whether it ran on the same sample as the water test — [International Electrotechnical Commission, 2013] defines both digits, and a report naming one number without saying which digit it tested has answered half the question.

Where does a sealed unit actually fail first?

The rating is a property of a new unit. Field failures concentrate in four places, and none of them is the housing wall: the charging-port cover, the button membrane, the seam between two moulded halves, and the motor shaft exit. Each is a moving part or an interface, and each degrades on a different schedule.

The practical consequence for a buyer is a specification that names the test, the condition and the frequency: IPX7 at 1 m for 30 minutes, on 100% of units at final inspection, with the batch record shipped. Anything less specific is a design intention rather than a control, and [Montgomery, 2020] makes the general point: a quality characteristic that is not measured on the unit being shipped is not controlled, whatever the drawing says.

Which IP rating does your market actually require?

Rating choice is a commercial decision more than an engineering one. Higher ratings cost more to engineer and more to verify per unit, and they constrain the housing: a submersible body needs a sealed port cover, which is the part customers most often break. 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 — IPX7, with the depth and duration stated.
• Cleaning claims. "Washable" is a claim about a jet, which points at IPX5 or above. "Rinse-safe" is the wording that matches IPX5 without overpromising.
• Retail channel. Some retailers have category-wide requirements that exceed what consumers would ask for; the requirement is usually written in the vendor manual, and it is cheaper to read it before tooling than after.
• Return economics. A warranty claim costs the unit, the freight and the review; on a 300-unit first order, a handful of ingress returns can exceed the margin on the batch.

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, and the certification pack for the report that proves it.

How do you tell a tested IP rating from a claimed one?

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.

There is one more question worth asking, and it is the one that separates a supplier who has run the test from one who has read about it: what happened to the units that failed. A batch report with a 100% pass rate on a sample that was never stressed is a filing exercise. A report that names the failures, the rework and the re-test is a control, and it is the only kind that tells you anything about the next batch.

How many units are tested, and which ones, is the same arithmetic as any other lot decision: how a sample decides a lot is the method, and a water test obeys it exactly as a cosmetic check does. A rating backed by one qualification sample is a statement about that sample.

References

1. International Electrotechnical Commission (2013). Degrees of protection provided by enclosures (IP Code), IEC 60529, Edition 2.2. Geneva: IEC.
2. Juran, J. M. & Godfrey, A. B. (1999). Juran's Quality Handbook, 5th ed. New York: McGraw-Hill.
3. Montgomery, D. C. (2020). Introduction to Statistical Quality Control, 8th ed. Hoboken, NJ: Wiley.