28/09/2016
vulnerable to anything more than rain/washing hands. IP67/68 is a gimmick. I am sick and tired of reading “This is water resistant! Not water proof!” so I decided to make a little write-up about water protection.
So first of all, “waterproof” or “water resistant” by itself means nothing. Nothing. It’s not like “water resistant” is against splashed and “waterproof” is for submersion. “Waterproof” does not mean that water damage is covered by the warranty. Furthermore, standards for watches, ISO 2281 and subsequent 22810 prohibit the use of term “waterproof” as confusing.
So let’s focus first on IP code which comes from IEC standard 60529. We all saw the marking IP67, IP68 etc. So what those number mean?
First digit is for solid particle protection. 0 is no protection, 1 to 4 is protection from objects larger than 50, 12.5, 2.5 and 1 mm (I will use metric units, sorry). Number 5 is “dust protected” which Wikipedia, for confusion I think, calls “dust proof”. Standard states that “Ingress of dust is not totally prevented, but dust shall not pe*****te in quantity to interfere with satisfactory operation of the apparatus or to impair safety”. Number 6, highest level of particle protection, means no dust what so ever in the enclosure. Easy.
Second digit is trickier. 0 for no protection is fairly obvious. 1 is equivalent of light rain. 2, 3 and 4 are different degrees of splashing water. Think washing your hands with different degree of sloppiness. Numbers 5 and 6 is water jets with specific flowrates. My back of the envelope calculations show that 5 is equivalent to my water tap in the kitchen that’s open in full. 6 is much stronger.
And now the popular numbers – 7 and 8. First one is up to 1 meter for 30 minutes. It does NOT mean that it will start leaking after 30 minutes. It just means that this is the test that was done and passed. Number 8 means test done for more than 1 meter (has to be specified) for a specified amount of time.
Now what is important about this, that if you have a device with IPX7 or IPX8 protection it is NOT automatically compliant with neither IPX5 or IPX6 – the water jets test!
You also need to remember, that all those tests are carried out at temperatures between 15 and 35 degrees C. (60F to 95F). This means that hot tub or a steamy shower is outside of those conditions. Higher temperature means softer rubber means less protection.
Let’s have a closer look at watches now. This industry has a long history of making water resistant watches. My Casio is rated at 20 bar for example. Per ISO 22810 it means that it was tested at 125% of this pressure -25 bar. This is equivalent to 250 meter deep water. Now that makes your 1 meter deep rated Xperia look silly. And you know that is even funnier? Look at the suggestions from watch manufacturers on what those ratings mean. Very often 3 bar (30 meters) rating is described as “everyday use. Splash/rain resistant. NOT suitable for swimming, snorkelling, water related work or fishing”. Other website describes 5 bar (50 meters) as “Suitable for everyday use and swimming but NOT poolside diving, snorkelling or water sports.” Oh – and you are required to service your watch every year and preferably pressure test it, because seals degrade over time.
Again, compare it to 1 meter (0.1 bar) rated Xperia… So what does IP67/IP68 mean? Not much. Mostly marketing and that it is slightly better than water-splash resistant.
Please keep your IP-whatever rated devices out of your showers, water taps etc. – they are not rated for that unless IPX5 or IPX6 rated. Keep your IP rated devices from the swimming pools, as 1 meter rating is very low. When you move your phone underwater you will generate dynamic pressure due to movement. Washing hands/rain is ok.
Warranty? What warranty. It is impossible to prove that you had all your flaps closed and even flap-less models can be easily water damaged under the sink – remember, no water jet rating. You may start to see water damage covered under warranty if it is 10 bar / 100m rated because then it actually is fairly difficult to damage such phone at home.
I hope you enjoyed the read. Drop me any questions that you might have.
edit: as pointed out in the comments, Xperia Z series is actually tested for IPX5 as well. This is tap like water jet. This makes it tougher than I originally thought, but still it is nowhere near the level of waterproofing seen in watches.
edit2: Sony (and later Samsung) by waterproofing their flagships made an awesome step change. My next smartphone will be at least IPX7. I am not bashing them for doing a lousy job, I am just saying to take the waterproofing for what it really is.
