Understanding Water Resistance in Watches

Water resistance refers to the level of pressure a watch can endure underwater at a certain depth without leaking or compromising its accuracy. The term "water resistant" is officially recognized by the Federal Trade Commission, which prohibits the use of "waterproof." It's important to note that water resistance and depth are not synonymous. A watch is tested at a specific depth while stationary and at a temperature range between 18°C and 25°C. Any movement in the water exposes the watch to varying pressures. For example, water pressure from a hose or activities like water sports can exceed the watch’s rated water resistance.

Watches come with varying levels of water resistance. However, it's essential to avoid wearing them in the shower or bath, as the chemicals in soaps and shampoos can damage the gaskets.

Water Resistance Levels and Their Meanings

Let's explore the different levels of water resistance measured in bars and what they mean. Manufacturers typically specify a model's water resistance rating using bars, atmospheres (ATM), meters (M), or feet, often marking the case back and dial with figures like 30ATM or 50M. Check out the links below each section for recommendations on the watches we stock—maybe one will catch your eye!

3 Bars / 30 Meters / 3 ATM / 100 Feet

• Can withstand water splashes (e.g., hand washing, rain). 
• Not suitable for swimming or submersion.

5 Bars / 50 Meters / 5 ATM / 165 Feet

• Can handle splashes and light swimming. 
• Swimming is possible, but should generally be avoided.

10 Bars / 100 Meters / 10 ATM / 330 Feet

• Suitable for snorkeling, scuba diving, and other water sports. 
• Safe to use in a variety of water activities.

20 Bars / 200 Meters / 20 ATM / 660 Feet

• Safe for scuba diving. 
• Should not be used for diving with helium unless equipped with a helium escape valve. 
• Likely more than most users need unless they are serious divers.

30 Bars / 300 Meters / 30 ATM / 1,000 Feet

• Typically a professional dive watch. 
• Suitable for deep-sea dives requiring helium.

50 Bars / 500 Meters / 50 ATM / 1,640 Feet

• Designed for extreme deep-sea diving.

60 Bars / 600 Meters / 60 ATM / 2,000 Feet

• Suitable for professional and technical diving. 
• Designed to withstand very deep underwater environments and significant water pressure. 
• Ideal for serious divers requiring high reliability in extreme conditions.

100 Bars / 1,000 Meters / 100 ATM / 3,300 Feet

• Upper-end professional dive watch. 
• Capable of withstanding extreme conditions. 
• Watches can be found with ratings as high as 400 bars or more.

If a watch is water-resistant, this will be mentioned on the dial or case back. If no specific depth is mentioned and the watch is labeled as water-resistant, it means it meets general water-resistant standards. However, water resistance is not a permanent feature. The gaskets around the crown, crystal, and case back can wear out over time and should be inspected regularly. For a general water-resistant watch, this inspection is often just a visual check. Applying silicone lubrication can help prolong the life of the gaskets and is typically done during battery replacement. Generally, a rating of 1 ATM is not considered an indication of water resistance and should not be treated as such.

It's important for watch owners to understand both the capabilities and limitations of their timepieces, as well as the true meaning behind any depth designations or the absence thereof. Owners should ensure that the seals are intact and that components like the case, crystal, crown, and back are securely and properly positioned, especially after the case back has been removed. Whenever a watch undergoes service, the gasket is lubricated with a silicone sealant to enhance water resistance.

As you go deeper underwater, the water pressure increases, requiring a watch to have greater water resistance. The quality of materials used and the precision of the manufacturing techniques directly affect how tight the tolerances are and how robust the casing is that protects the watch's movement.