What Makes a Device Waterproof or Water-Resistant?
The new crop of flagship Androids boast of letting you take photos in the pool or not worrying about your handset when it rains. Even the next iPhone is rumored to be safe from water damage. Sounds cool, doesn’t it?
But they aren’t waterproof. No, these devices are water-resistant, and there’s a difference.
It’s not just phones, of course. As we move into a world where wearable tech can change our lives , we need our gadgets to be indestructible. Water is the biggest threat in this, as we are exposed to it with rain, spilled glasses, pools, and whatever else you can think of.
So you often hear from manufacturers about how a smartphone is “waterproof” or how a fitness band is “waterproof”, but that’s the wrong word — and if you aren’t careful, this simple linguistic bumble could cost you.
Waterproof vs. Water-Resistant
Simply put, waterproof indicates an inability for water to ever get inside while water-resistant indicates that water can get inside under certain conditions. No consumer technology out there is waterproof. They are all water-resistant.
It’s a subtle but important difference. Yes, your phone will probably be fine in the rain, but you can’t go deep-sea diving with it. Yes, that smartwatch may show you the time underwater, but you can’t press its button at the same time because it’ll open the seal and allow water to enter.
That being said, let’s dive a little deeper into water resistance and the two standards used to indicate under what kind of conditions the device will repel water: ATM and IP.
ATM: Used Mostly for Wearables
ATM stands for atmosphere. One atmosphere is roughly the ambient pressure exerted on you when you’re on the surface of water. Dive 10 meters below seawater and that’s two atmospheres, as the water’s pressure is added to the original ambient pressure. Every 10 meters adds another ATM.
Smartwatches and fitness bands like the Pebble (read our review ) usually mark their water resistance in ATMs. The Pebble, for instance, has a water resistance of 5 ATMs, which means it can be used by recreational divers, or for swimming in a pool, or pretty much any activity within that limit.
There is no standardized test to determine the ATM of a wearable device, although some watches adopt the ISO:22810 standard. As an end user, this is jargon that you don’t need to worry about.
The bottom line is that if a wearable device uses ATMs to mark its water resistance, it means that’s how deep you can go into the water while wearing it.
But there is one limit that isn’t explicitly stated on wearables: these devices are water-resistant only as long as the various seals remain in tact. You can’t press any buttons when submerged.
It’s an issue with all water-resistant watches. You can’t do anything to break the seal, even if that action is how you would normally use your device. The second you break the seal, water will seep in.
IPxx: Used Mostly for Phones
Unlike wearables, smartphones have standardized tests for water resistance that are set by the International Electrotechnical Commission (IEC). These are called International Protection or Ingress Protection codes, commonly denoted as IP followed by two digits.
For example, the Samsung Galaxy S7 Edge (read our review ) has a rating of IP68.
In those two digits, the first digit refers to dust protection, in which 6 is the highest rating (and most smartphones achieve this today). The second digit refers to water protection, in which 9 is the highest rating (but most phones top off at 7 or 8).
Here’s a quick list of what each water resistance number indicates:
- 1: Dripping water has no effect.
- 2: Dripping water has no effect even when falling at an angle of 15 degrees from vertical.
- 3: Spraying water has no effect even when coming at an angle of 60 degrees from vertical.
- 4: Splashing water from any direction has no effect.
- 5: Water jets from a 6.3mm nozzle have no effect.
- 6: Water jets from a 12.5mm nozzle have no effect.
- 7: Submerging up to 1 meter for 30 minutes has no effect.
- 8: Submerging more than 1 meter for more than 30 minutes has no effect.
- 9: High temperature, high pressure water sprays have no effect.
Of these, you’re likely never going to encounter the last one — the important ones are 4 through 8. The unfortunate thing is that just because a device has been tested for one number doesn’t mean it’s been tested for the other numbers below it.
So even though the Galaxy S7 Edge is IP68, which indicates a water resistance of 8, that doesn’t mean it necessarily rates as 5 or 6 (which means it could be susceptible to water jets). That’s why some devices like the Sony Xperia Z5 boast both IP65 and IP68 ratings.
But don’t worry, we’re only talking technical here. Generally, any device that is rated as 5, 6, 7, or 8 will protect against the first four as well, i.e. drips, sprays, and splashes.
What all of this means is that when you look at any water-resistant phone, you should check the last number in the IPxx rating. The higher the number, the better the protection. And if you want to go scuba diving, you’re better off buying a GoPro or other action cameras instead.
And before you ask, no, there is no external case that makes a device completely waterproof either. There are some excellent water-resistant cases for the iPhone , but they also have a similar IP68 or so rating.
The Limitations of “Waterproof”
By now, you already know that “waterproof” actually means water-resistant. There are precise conditions under which it gives you that protection, so let’s find out the limitations of waterproof tech so you can know exactly what you need to be wary of.
Seals and Buttons: If your device has any flaps, close them. If your device has any buttons, don’t press them. Leaving a flap unfastened or pressing a button will break the rubberized seal formed inside the device, thus letting water enter. However, some phones and case makers do let you press buttons underwater, so make sure you read whether yours allows it.
Fresh Water Only: Can you take your phone into the sea? Yes. Should you take it into the sea? No. All of the IP tests are performed with fresh water, not with sea water. In fact, salt deposits can damage your phone beyond repair, so it’s best to keep your waterproof phones away from the sea. In case you do take it in, rinse it completely with fresh water before using it again.
No Other Liquids: All the IP tests only protect against water, not coffee spills and dunks in muddy water. In such cases, do what you’d do when spilling coffee on your laptop : switch off the phone, clean it up, remove the battery if possible, dry it thoroughly, and then switch it back on once fully dry.
It’s About Protection, Not Fun
What most of us forget about these waterproof phones and cases is that they are meant to protect your device, not enable new features. The features are a bonus, so don’t be disheartened if they don’t work.
For example, don’t go by the advertisements touting how you can dive into the pool and take underwater snaps of your friends. Touchscreens don’t work well underwater, so it won’t register your taps anyway. There are some exceptions like the Sony Xperia Z5+, but those are truly exceptions.
Waterproofing is a protection measure, not a utility feature. When your phone gets wet, you should still follow the recommended steps to save a wet phone : switch it off, let it dry, and then switch it back on. Waterproofing isn’t flawless, so why risk it?
To sum up, waterproofing isn’t real. What you actually get is water resistance — but that’s good enough in most cases. The question then becomes whether the phone itself should be waterproof or if you should get a sleek device and go for a rugged cover instead.
In your opinion, what’s the better option? Should someone buy a waterproof phone and forget about a cover, or purchase any phone they like and add a rugged waterproof case?