TraviaTechPie Review

The Story

Here’s a scene that plays out constantly. Someone buys a shiny new smartwatch, sees “5ATM” or “IP68” on the spec sheet, thinks “great, it’s waterproof,” and then a warm shower or a jump into the pool later, the watch is dead. The rating was real. The expectation was wrong.

The same IP logic applies to earbuds — see how to choose wireless earbuds.

Water resistance is just one spec to weigh — it also pays to understand what each health sensor really measures.

The problem isn’t that any of these numbers lie. It’s that they answer a much narrower question than the one you’re actually asking. A water resistance rating tells you how a device behaved in one specific lab test, under one specific set of conditions. What you want to know is “can I swim/shower/dive with this?” — and those are not the same thing. So let’s decode the labels properly, because once you see what each one is actually measuring, the buying decision gets a lot clearer.

There are really three families of markings you’ll run into on wearables: ATM (atmospheres, a pressure rating), IP codes (the two-digit ingress protection numbers like IP68), and, on the high end, dive certifications like EN13319. They come from different standards bodies, they test different things, and — this is the part that trips everyone up — a higher number in one system doesn’t automatically beat a number from another. Let’s take them one at a time.

ATM: a pressure number, not a depth promise. When a watch says 5ATM, it passed a test under ISO 22810, the standard that governs water-resistant watch markings. 5ATM means the watch withstood static pressure equivalent to 50 meters of water; 10ATM is 100 meters. But read that word “static” carefully, because it’s doing all the work. The test is done with the watch motionless in still water. The moment you start moving — an arm slicing through a freestyle stroke, a dive off the pool edge, a jet-ski smacking the surface — you generate dynamic pressure that can spike far above the static number. That’s why 5ATM is generally treated as “fine for swimming laps and getting splashed,” while snorkeling and any forceful water entry is where people start recommending 10ATM. The 50m on the box was never a depth you could visit. It was a lab pressure the seals happened to hold.

IP codes: two digits, two completely different jobs. An IP rating like IP68 comes from IEC 60529, and the two digits are independent. The first digit is dust and solid-particle protection, on a scale of 0 to 6. The second is water protection, 0 to 9 (with a special “9K” tier). So IP68 means “6” — fully dust-tight — plus “8,” which is continuous immersion beyond one meter. Here’s the catch on that second digit: the standard doesn’t fix the depth or duration for level 8. The manufacturer defines the test conditions (often something like 1.5m for 30 minutes) and states them. So two IP68 devices can have quietly different real-world limits. IP68 is not a single guaranteed number.

Now the one that confuses everybody: IP69K is not simply “better than IP68.” The “9K” tier tests something different — resistance to close-range, high-pressure water jets at high temperature, roughly 80–100 bar of pressure and water at about 80°C. It was written for things like industrial equipment that gets steam-cleaned. Passing IP69K does not automatically mean a device passed the deep-immersion IP68 test, and vice versa — they’re separate procedures. That’s exactly why rugged gear sometimes lists both (IP68/IP69K): they had to certify each one on its own. If you only see IP69K, don’t assume prolonged submersion is covered; if you only see IP68, don’t assume hot pressure-washing is.

And watch the first digit too. A rating like IP48 looks reassuring until you decode it. The “8” is great — deep water immersion. But the “4” only means protection against solid objects 1mm and larger. The 1mm test uses a wire probe; it is not a fine-dust test at all. Fine sand and powder can still get in. This isn’t hypothetical — it’s precisely the situation with the flip and fold phones that carry IP48: water-sealed, but explicitly not rated dust-tight. On a wearable you drag through gym chalk, beach sand, or trail dust, that first digit matters more than the marketing lets on. I unpacked how this plays out on foldables in the foldable buying guide.

Dive certifications: a feature license, not a deeper seal. At the top end, some watches — the Galaxy Watch Ultra line, Apple Watch Ultra, dedicated dive computers — carry EN13319, the European standard for diving depth instruments, often quoted alongside “recreational diving to 40 meters.” Two things worth knowing. First, EN13319 certifies the depth-and-time measurement instrument — the ability to track depth, dive time, and temperature accurately — under EU Regulation 2016/425. It’s a certification of the diving function, not a separate promise that the case survives any depth. The case’s water limit is still expressed through ATM. Second, the standard covers the hardware measurement, not the decompression software logic — that’s on the manufacturer. So “40m dive certified” is a real, meaningful capability, but it’s a different claim than “this case is waterproof to X.” I dug into how this shakes out on the Ultra tier in the Galaxy Watch 9 vs Ultra 2 breakdown.

Here’s a quick reference for the labels you’ll actually see:

The Takeaway

The mental shift that fixes all of this is small but powerful: stop reading these ratings as a quality score and start reading them as a use-case license. Bigger number does not mean better watch. It means “cleared for a specific activity.” A 5ATM band is genuinely fine for a lap swimmer and pointless overkill nobody needs to pay extra for if you only shower with it off. A diver needs EN13319, and no amount of IP68 substitutes for it. The rating isn’t a bragging stat — it’s a permission slip for one thing.

Two traps are worth burning into memory. First, the systems don’t nest. IP69K sitting above IP68 in your head is the single most common mistake, and it’s wrong — they’re different tests, which is why serious gear lists both. Same logic tells you to actually read the first IP digit, because an IP48 device is sealed against water but not against the fine grit a wrist magnet for dust like a watch will absolutely meet. Second, none of these ratings survive hot water, soap, or high-pressure spray unless the label specifically says so. Heat and surfactants degrade the seals; a 5ATM swim rating says nothing about a steamy shower.

And the quiet one nobody prints on the box: water resistance is not permanent. Gaskets and adhesives age, and every knock, temperature swing, and battery swell chips away at the seal. A three-year-old watch is not as watertight as it was on day one. If the marketing rounds all of this off to a friendly “waterproof,” that’s the gap you’re now equipped to see through. Match the rating to what you’ll actually do in the water, read both digits, and treat the number as a starting condition — not a lifetime guarantee.

This article is for general information only. Because seals degrade over time, always follow your manufacturer’s current water-exposure guidance for your specific model.

Photo: Indra Projects / Unsplash