Water resistance is an important feature to consider when choosing a watch. The terms "ATM" or "atmosphere" are commonly used to describe a watch's water resistance level. These terms refer to the pressure a watch can withstand when submerged in water. There are four standard ratings:
- 3 ATM (30 meters/100 feet): Watches with this rating are suitable for everyday use and can handle accidental splashes, rain, or brief immersion in water, such as washing hands or light surface swimming. However, they are not suitable for activities like diving or snorkeling.
- 5 ATM (50 meters/165 feet): Watches with this rating offer higher water resistance. They can handle the abovementioned activities and are suitable for recreational swimming, including surface snorkeling. However, they are not intended for diving or prolonged submersion.
- 10 ATM (100 meters/330 feet): Watches with this rating are highly water-resistant and suitable for recreational water activities, including swimming, snorkeling, and even recreational diving. They can handle the pressure these activities exert but are not designed for professional or deep-sea diving.
- 20 ATM (200 meters/660 feet): Watches with this rating offer a significantly higher water resistance level than the previous ratings. They are designed to withstand more demanding water activities, including swimming, snorkeling, recreational diving, and professional diving (depending on the specific model). However, it's important to note that not all 20 ATM watches are created equal. Some models may be specifically designed for professional diving and have additional features, such as helium release valves or enhanced seals, to handle the extreme conditions associated with deep-sea diving. If you're considering using a watch with a 20 ATM rating for diving purposes, consult the manufacturer's specifications and guidelines to ensure it's suitable for your intended use. Regular maintenance and periodic checks by a professional watchmaker are essential to maintain the watch's water resistance. Remember that while a watch may be water-resistant, it's always a good practice to avoid exposing it to extreme temperature changes, hot water, or chemicals, as these can compromise its water-resistance capabilities.
To maintain water resistance, it's important not to press any buttons underwater unless your watch is indicated as 200m water-resistant.