Understanding ATM Water Resistance Ratings in Waterproof Watches

Introduction

Water resistance ratings, such as 3ATM, 5ATM, 10ATM, and 20ATM, are common terms associated with waterproof watches. These ratings indicate the watch’s ability to withstand water pressure at specific depths. However, their real-life implications often differ from the technical specifications.

In this guide, we will decode what these ATM ratings mean, their suitability for activities like swimming or diving, and how to choose a watch that meets your water resistance needs.

What is ATM?

• This parameter is specified in units of pressure (i.e., atmosphere or ATMs) or water depth (in units of meters) up to which the watch works satisfactorily.
• Atmospheric Pressure: At sea level, the atmospheric pressure is approximately 1 atmosphere (1 ATM). This is the pressure exerted by the weight of the air above us.
• Pressure Measurement: 1 ATM is equal to:
  • 101.3 kPa (kilopascals)
  • 1013.25 hPa (hectopascals)
  • 14.7 psi (pounds per square inch)
  • 29.92 inHg (inches of mercury)
• Water Resistance Ratings: ATM ratings are used to indicate how much pressure a device can withstand before water starts to seep in. These ratings are based on the pressure that the device can endure, which is roughly equivalent to being submerged to a certain depth in water.
• Conversion to Depth: Each ATM unit roughly equates to the pressure experienced at a specific depth in water.

Let’s look at some specific examples:

3 ATM

• 3 ATM means the device can withstand pressure equivalent to a depth of 30 meters or 100 feet (3 times the atmospheric pressure at sea level).
• This rating means the watch can withstand splashes of water and rain, but it is not suitable for swimming or submersion. It’s ideal for everyday use and accidental exposure to water.

5 ATM

• 5 ATM means the device can withstand pressure equivalent to a depth of 50 meters or 165 feet.
• With a 5ATM rating, the watch is suitable for swimming in shallow water. It can handle activities like showering or washing your car, but it’s not designed for diving or snorkeling.

10 ATM

• 10 ATM means the device can withstand pressure equivalent to a depth of 100 meters or 330 feet.
• A watch with a 10ATM rating is suitable for swimming, snorkeling, and other water sports that do not involve high-speed water or deep submersion. It offers better protection against water and can handle more rigorous water activities.

20 ATM

• 20 ATM means the device can withstand pressure equivalent to a depth of 200 meters or 660 feet.
• This rating indicates that the watch is suitable for high-impact water sports and recreational scuba diving. It is designed to withstand significant water pressure and can be used for diving, although it may not be suitable for professional deep-sea diving.

It’s important to remember that there is no single watch in the world which is 100% waterproof due to the fact that moisture can potentially leak into the case and affect its functioning. These ratings are designed to indicate how well one watch can handle water pressure compared to another.

The popular smartwatch manufacturers across the globe include Xiaomi, Huawei, Fitbit, Samsung, etc.

Water Resistant Ratings Table

Water-resistant levels for smartwatches are specified from 2 ATM, 3 ATM, and up to 20 ATM. Watches designed for divers are manufactured to withstand depths beyond 200 meters.

The following table shows popular ATM ratings including 1 ATM, 2 ATM, 3 ATM, 5 ATM, 10 ATM and 20 ATM.

NOTE: It’s important to note that these ratings are based on static pressure tests. Actual water resistance can be affected by temperature changes, aging of seals, and exposure to chemicals like soap or chlorine. Always follow the manufacturer’s guidelines for water resistance care and maintenance.

Conclusion

Understanding water resistance ratings like 3ATM, 5ATM, 10ATM, and 20ATM is essential for selecting the right watch for your lifestyle. While 3ATM is ideal for splashes, higher ratings like 20ATM are suited for professional diving. By knowing these distinctions, you can ensure your watch remains durable and functional during water-related activities, giving you peace of mind and value for your investment.