IPX7 is easily read as "waterproof and dust-protected". The rating says something about water only. The 7 refers to temporary immersion, and the X in first position means that no level was assigned for dust. This article explains what the X means under IEC 60529, what IPX7 and IPX8 test, and why nothing follows from the rating about dust. It also includes a table with the protection ratings of five devices from our datasheets. How the digits are built up is covered in the overview IP protection classes. This article is about what is missing when a digit is missing.
The IP code consists of the letters IP and two digits. The first digit covers contact, foreign objects and dust, the second covers water. This is set out in IEC 60529, which applies in Germany as DIN EN 60529. If an X stands in one position, no protection level was assigned for that position. Wikipedia summarises it like this: the digit is replaced by X when there is not enough data to assign a level.
IPX7 therefore means: first position without a rating, second position 7. The counterpart is IP5X: first position 5, second position without a rating. In our range the Durabook S15AB is written this way. The table further down shows what that means for the statement in the datasheet.
Two readings suggest themselves, and both are wrong. The first is that IPX7 means the device has no dust protection. The second is that IPX7 means the device is dust-protected anyway. The manufacturer Jabra writes in a post dated 25 October 2023 that the X is not the same as a 0. It means that the manufacturer did not specifically test the product for protection against solid objects.
In the standard's table the 0 stands for "no protection". The X stands for something else, namely a position that was not assessed. A device with IPX7 can therefore be sealed or not. The rating does not prove it, and so for a purchasing decision the dust protection is unknown.
For a device with an X it is worth asking the manufacturer: was the position tested, with what result, and is there a test report? Without that answer the position counts as open.
The 7 means protection against temporary immersion. According to Wikipedia the test lasts 30 minutes. The lowest point of the enclosure lies 1000 mm below the water surface, or the highest point 150 mm below it, whichever is deeper. The test is passed if no harmful water gets in. It uses fresh water. Protection against salt water and other liquids is therefore not assured. The details are in IP67 in detail.
The 8 stands for continuous immersion, and here the standard sets no fixed test. According to Wikipedia the manufacturer determines the depth, and the duration is agreed with the manufacturer. Both should be above the values of IPX7, and Wikipedia gives up to 3 m as the usual upper limit. It follows that IPX8 without a stated depth and duration is incomplete. Two devices with IPX8 are only comparable when both values are given next to the rating. The article IP68 in detail covers this point at length.
Water and dust are tested separately, with separate set-ups. For the dust test of digit 6, the enclosure maker ROLEC describes a mixture of talcum powder and air, a negative pressure of at most 2 kPa inside the enclosure, and a test that runs for 8 hours. The water test of digit 7 takes place in a tank. Anyone who has only tested in the tank has measured nothing about dust.
The device may still be dust-tight. The rating just does not prove it, and a datasheet or a tender cannot rest on something unproven. This matters as soon as dust is part of the job: in the workshop, in the warehouse, on the building site, or in forestry and farming. There the first digit 5 or 6 is the rating to look for.
The difference to IP67 and IP68 needs only one sentence here. The second position is the same water test in IPX7 and IP67. IP67 also says that the dust test was passed at the highest level. IPX7 says nothing about it.
The water side has a gap too. Beyond 6, the levels of the second digit are not cumulative. According to Wikipedia a device with IPX7 is therefore not necessarily tested to IPX5 or IPX6 as well, that is, not against water jets. Whoever meets both lists both ratings with a slash, for example IPX5/IPX7. What the water jet test requires is shown in the article IP66 in detail.
The following table sets side by side the five notations that occur in this article:
| Rating | Dust | Water | Stays open |
|---|---|---|---|
| IPX7 | no rating | temporary immersion | dust, water jets |
| IPX8 | no rating | continuous immersion | dust, water jets, depth and duration if not stated |
| IP5X | protected against dust in harmful quantity | no rating | water of any kind |
| IP67 | dust-tight | temporary immersion | water jets, continuous immersion |
| IP68 | dust-tight | continuous immersion | depth and duration if not stated |
For a complete rating, three things therefore have to come together:
Of the 45 datasheets we hold on robustbook.bitblade.io, none states IPX7 or IPX8. One datasheet has an X, and in second position: IP5X on the Durabook S15AB. The other 44 give both digits. The following table shows five of them as they appear in the "IP rating" line, and what each digit says:
| Device | Display | Rating | First digit (dust) | Second digit (water) |
|---|---|---|---|---|
| Durabook S15AB | 15.6 inches | IP5X | 5: protected against dust in harmful quantity | X: no rating |
| Durabook S14I | 14.0 inches | IP53 | 5: protected against dust in harmful quantity | 3: spraying water up to 60° from vertical |
| Fieldbook F57G2 | 5.7 inches | IP67 | 6: dust-tight | 7: temporary immersion |
| Getac ZX80 | 8 inches | IP67 | 6: dust-tight | 7: temporary immersion |
| Archos X67 5G | 6.67 inches | IP68, IP69K | 6: dust-tight | 8: continuous immersion; 9K: high-pressure and steam-jet cleaning |
The Durabook S15AB is the mirror image of IPX7: it says something about dust and nothing about water. Whether it tolerates water does not appear from the line, and from the line alone one may infer neither protection nor lack of it. For the Archos X67 5G, the core data table gives no depth and no duration for IP68. For a comparison with other IP68 ratings, one value is therefore missing. Among the laptops in our range, none carries a rating with 7 or 8 in second position. The devices with immersion protection are rugged tablets and the smartphone.
No. The water test is the same, but IP67 also contains the dust test with the result "dust-tight". With IPX7 there is no rating for it.
That is not proven. The manufacturer has stated no level for dust protection. Anyone who wants to use the device in a dusty environment should ask the manufacturer about the first digit.
That is not assured. IPX7 is not a water jet test, and levels 5 and 6 are not contained in the 7. Only a rating such as IPX5/IPX7 covers both cases.
For immersion, yes, because depth and duration are meant to be above the values of IPX7. How far above is for the manufacturer to set. Without those two values the rating is incomplete.
The first digit 5 means protected against dust in harmful quantity. The X in second position means that no rating is given for water. In our range the Durabook S15AB carries this rating.
IPX7 is enough for a single question: does the device survive brief immersion? Where dust plays no part, that is a usable answer. Anyone choosing a device for the workshop, warehouse, building site or outdoor work should accept only ratings that state the first digit.
From our range, the Fieldbook F57G2 and the Getac ZX80 (both IP67) and the Archos X67 5G (IP68) suit immersion with a dust-tight enclosure. None of the three carries a second digit of 5 or 6 for water jets, the Archos has IP69K for that, and no device in the range carries IP66 and IP67 together. Anyone who wants immersion and water jets both documented will find no device with both ratings among the 45 datasheets, and should clarify beforehand whether the manufacturer of the desired device can supply a test report for both tests. For laptops with immersion protection, none of the devices fits. The Durabook S15AB should be chosen only if water plays no part in the job, because its rating leaves that open.
We are glad to work out with you, from the datasheets, which rating is enough for your use.