No. Most watches have some sort of water-resistance. There are a variety of ways to make a watch water-resistant. All such watches use rubber gaskets or “O” rings to seal the case back. A watch with a back that screws onto the case provides a higher degree of water resistance.

A watch marked as water resistant without a depth indication is designed to withstand accidental splashes of water only. Increasingly higher acceptable depths, usually indicated in meters, indicate higher levels of water resistance.

Most water-resistant watches indicate their level of water-resistance on the dial or on the back of the case. The most common designations are in feet or meters. Sometimes the abbreviation ATM, short for “atmosphere” is used and relates to atmospheric pressure. One atmosphere is equal to 10 meters or 33 feet of water pressure. The term “bar” often used in Europe is the equivalent of “atmosphere”. Most watches on the market are water-resistant to 30 meters.

Here is a chart to show examples of water-resistance:


*NOTE: The criteria for divers water-resistance are different from the criteria for standard water-resistance. The divers water-resistance takes into account underwater pressure that comes with deep sea diving. Hence, a watch that is rated at 200 meters for skin diving is not the same as a watch that is rated at 150 meters for scuba diving.

In addition to the water-resistance rating of 100 meters, watches should have a screw-down crown (also known as ‘screw-lock’ or ‘screw-in’ crown) to ensure maximum water-resistance during swimming. To maintain the integrity of the water-resistant system, periodic maintenance is required. The gaskets and rings are subject to wear and tear and should be replaced from time to time. This is part of the normal service work that should be done on any watch every 2 years.