When you’re shopping for a new watch, one of the most important factors to consider is how water-resistant or waterproof it is. These two terms are often used interchangeably among watch enthusiasts, but they don’t mean the same thing. Wondering what’s the difference between the two? Most people don’t know the distinction but it’s an important factor to understand before making a watch purchase.
Here’s a breakdown of everything you need to know about water-resistant vs. waterproof watches so you can decide which one is right for you.
In the watch industry terms, water resistance is simply the ability of a watch to withstand water pressure. The rating you see on a watch doesn’t reflect the depth at which water can be safely introduced to the timepiece but instead how much pressure it can withstand. Watches are designated a specific water resistance classification or ATM rating (or atmosphere rating).
The ATM rating specifies how many meters or feet a watch can be “safely” submerged in water without being damaged. For instance, one ATM is equivalent to approximately 10 meters, so 10 ATM should be 100 meters. However, it’s important to understand that this doesn’t mean you can take your watch diving to 100 meters.
Again, the ATM rating is a measure of the static pressure that a watch can withstand, not how it will perform under dynamic conditions such as when you’re swimming or diving. Watches are also subjected to other forces, such as centrifugal force and vibration. So even if a timepiece has a high ATM rating, it doesn’t mean that you can take it for extended periods of swimming or diving without impacting its functionality.
A Simple Breakdown of the ATM Designations
Whether you own the latest model of a water-resistant watch or an everyday timepiece, you’ve likely hopped into the shower, dived into a swimming pool, or even walked in the rain while wearing a watch. The water-resistance rating of your timepiece determines if your wristwatch or smartwatch will work properly despite being exposed to water or moisture.
Here’s a breakdown of what the most common water-resistance ratings mean:
- 3 ATM/3 Bar/30M – This is perhaps the most common water resistance rating you would expect to encounter on most fashion timepieces. Although wearers of such timepieces claim they have no desire to dive below 30 meters underwater and, as a result, feel comfortable showering or even submerging them in water, you should never do so in reality. 3 ATM watches are only suited for accidental daily splashes, rainwater, and washing one’s hands as they have delicate enclosures.
- 5 ATM/5 Bar/50M – Although few people will ever descend as far as 50 meters, even if the opportunity arose, these timepieces would not be able to accomplish it. They will, however, tolerate being gently immersed for short periods with no problem. They should also be suitable for use in the pool but don’t overdo it with swimming, diving off a board, or going to the jacuzzi.
- 10 ATM/10 Bar/100M – These watches should be feasible to do real water activities like swimming, scuba diving, snorkeling, sailing, and so on. This is the type of water resistance you should be looking for in any daily wear watch for added protection. Most luxury or fine watches will have this level of water protection.
- 20 ATM/20 Bar/200M – Watches with a 20 ATM rating are designed for more extreme aquatic sports and activities, such as diving or surfing. They can withstand greater pressure and will likely still function if you take them swimming, snorkeling, or even simply diving in shallow waters.
- 30 ATM/20 Bar/300M – This level of water resistance is ideal for diving at deeper depths, although it’s not certified to the world standards of an ISO 6425 diver’s watch. This rating is ideal for most water sport enthusiasts, but it’s not suited for professional diving.
- ISO 6425 Diver’s Watch – A depth rating is usually included with an ISO rating (100m, 200m, 300m, etc.), which means your watch has been certified by the manufacturer to withstand these depths. For instance, the Seiko SKX007, the Seiko SDB076, and the Casio WSD-F20 are three high-quality divers’ watches that can withstand any form of scuba diving. Any other diving activity that isn’t saturation diving is deemed safe by the watchmaker.
- ISO 6425 over 300m Diver’s Watch – Over 300 meters, an ISO rating of 6425 is usually appropriate for saturation diving (helium-enriched environment).
The first thing you need to know is that no watch is 100% waterproof. The term “waterproof” was used by watchmakers back when they created a watch that could survive water pressure up to 100 meters deep. But today, those “waterproof” watches can only be considered ‘water resistant’ because it can’t be guaranteed that the watch will still work after being submerged deep in water.
While you’re likely to come across watches that are marketed as waterproof, the term is actually illegal for watchmakers to use. This is because of a law established by the Federal Trade Commission (FTC). In 1960, it was ruled out that watches cannot be described using this term unless they were “watches which, by reason of their construction, will withstand water pressure at depths specified in an applicable standard.”
This law is still in effect to this day, and the FTC can take legal action against any watchmaker that uses the word “waterproof” on their products without meeting the requirements. In short, there are no fully waterproof watches, only watches with varying degrees of water resistance.
Taking Care of Your Water-Resistant Watch
If you want your watch to last for decades and hold its value, then take care of it by following these guidelines:
- Only operate your regular wear watch in dry environments
- If your watch gets wet, gently wipe it down with a cloth and allow it to air dry completely before putting it back on
- Avoid exposing your watch to extreme temperatures (either hot or cold)
- Never use harsh chemicals or solvents to clean your watch
- For leather watch bands, use a leather conditioner every few months
- Store your watch in its original box or pouch when not in use
- For watches rated for regular water use like diving or water sports, be sure to read the manufacturer’s guidelines
If you’re looking for a timepiece that will stand up to more rugged conditions, then you’ll want to invest in a watch that is “water-resistant” to 100 meters or more. These watches are designed for adventure and made from stronger materials like stainless steel, titanium, and ceramic so they can endure the elements with ease.
Choose a Watch for Your Lifestyle
If you’re looking for a watch that you can wear while participating in water activities, it’s important to decide what level of water protection you need. For this, a 10 ATM/10 Bar/100M or above watch rating is recommended. But if you are just looking for a day-to-day watch that matches your attire and can still work fine even after being exposed to the rain or splashed while washing your hands, then a 3 ATM/3 Bar/30M water-resistant watch is perfect for you.
Understanding the difference between a water-resistant and a waterproof outdoor watch can help you make the most out of your next purchase. You don’t want to be carried away by a watch’s water-resistant label and end up ruining your timepiece. So, make sure to do your research and know what you’re buying before investing in a new watch.