Beginners Guide to Watch Waterproof Testers

Written by: Maz P
Updated on:
Diving With a Watch

Water resistance in watches is a fascinating topic. Originally made for divers to track their time underwater, waterproof watches are now increasingly sought after for recreational water-based activities and even just day-to-day life. Water is a watch’s enemy with the ability to damage the inner parts, cause rust and lead to costly repairs. It is therefore crucial that if you use your watch for anything water-based or if your watch will touch water at any point, to make sure it’s waterproof.

Most watches stay waterproof for years but the resistance is subject to wear and tear over time, just like any watch component. If you have any waterproof watches in your collection, watch waterproof testers could be an essential tool to ensure that your waterproof watch stays in excellent conditions and continues to perform well underwater.

Waterproof Definition

Swimming with a watch

Waterproof, in the context of waterproof watches, refers to the watch’s ability to resist pressure and the entry of water. A watch labeled as waterproof is designed and constructed to withstand water exposure without allowing it to seep into the watch’s inner components.

The level of waterproofing is usually indicated by a water resistance rating, measured in meters or atmosphere (ATM) which indicates the depth to which the watch can be safely exposed to water pressure without sustaining damage. These days, new watch releases are often defined as ‘water resistant’ rather than waterproof but the typical definition remains the same.

Water Resistant vs Waterproof Watches

Water resistant and waterproof watches are terms often used interchangeably. It is increasingly common that newly released watches that would previously have been defined as waterproof are not labeled as water resistant. This is to distinguish the differences in water resistance.

Water resistant watches are designed to handle limited contact with water. They typically have a lower water resistance rating such as 3 ATM or 5 ATM which indicates the depth to which they can endure water pressure without leaking. These watches can handle activities like handwashing or minor splashes but they are not meant for swimming, diving or prolonged water immersion.

Truly waterproof watches are constructed to prevent water leaks even at significant depths. These watches often bear higher water resistance ratings for example 10 ATM or 20 ATM making them suitable for swimming, snorkeling or even scuba diving. Waterproof watches undergo rigorous testing to ensure their durability under water-related stress.

Ultimately, when deciding between water resistant or waterproof watches, it’s essential to evaluate your intended activities. A water resistant watch can handle everyday exposure but if you plan to engage in water activities beyond basic splashes and daily activity, investing in a genuinely waterproof watch with a higher water resistance rating is the safer choice.

Watch Waterproof Ratings

The level of water resistance varies by watch and if you are on the hunt for a water resistant or waterproof watch, you may be unsure which rating meets your needs. Watch waterproof ratings can be shown in meters but are more commonly rated in ATM. ATM is an abbreviation of atmosphere and identifies the maximum depth at which your watch can withstand water pressure. 1 ATM is equivalent to 10 meters and the higher the ATM number, the greater the depth your timepiece can withstand before any water leaks.

Watch waterproof ratings vary but there are some that are more common than others. Below you will find a list of the most common ATM ratings along with the equivalent in meters and the best usage for this rating. This guide will help you identify your watch usage and the level of protection you need against water pressure.

ATM RatingEquivalent in MetersUsage
1 ATMUp to 10 metersDay to day use with enhanced protection against occasional splashes
3 ATMUp to 30 metersResistant to rain, showering and accidental submersion
5 ATMUp to 50 metersSuitable for shallow swimming, snorkeling and bathing
10 ATMUp to 100 metersSuitable for deeper swimming, snorkeling and watersports
20 ATMUp to 200 metersBest suited for diving and intense water-based watersports

Do Watches Need Pressure Testing?

It is highly recommended to pressure test your watch at least once per year as this is an integral part of your watch maintenance routine. This practice ensures the ongoing water resistance of your timepiece and prevents potential complications that could arise from moisture infiltration as the watch ages. An annual test is advised for waterproof watches that are used day-to-day rather than for regular water-based activities.

For individuals who frequently engage in activities involving prolonged water exposure such as swimming, diving or water sports, more frequent testing is recommended. This gives you peace of mind that your watch is going to continue to perform when exposed to water pressure.

An additional step to consider is the regular replacement of gaskets. These small but essential components play a pivotal role in maintaining a watch’s water resistance by forming protective barriers where different parts of the watch meet. By replacing gaskets annually, you enhance your watch’s defense against water leaks. This proactive approach minimizes the risk of waterproof deterioration due to repeated contact with water.

Incorporating both regular pressure testing and gasket replacement into your watch maintenance routine not only safeguards your watch’s performance but also extends its longevity.

Do I Need a Watch Waterproof Tester?

Even if your watch is waterproof or water resistant, if you plan to swim, dive or expose your watch to water, it’s recommended to have it undergo a pressure test regularly. Whilst you can ask a professional watchmaker to assist you and book in for a pressure test, regular testing can be an inconvenience and it is therefore a lot easier to purchase a watch waterproof tester.

Having your own tester is valuable because seal failures can occur unexpectedly and this provides you with the flexibility to test your watches whenever you need to. Plus, getting a watch pressure tested by a local watchmaker could set you back $40-$100 for a single test.

However, you can purchase watch waterproof testers for under $100 and use it repeatedly so it makes more financial sense to invest in your own. A waterproof tester could prove to be a worthwhile investment and a great addition to your watchmaker’s toolkit.

Salmue Watch Waterproof Test Tool Salmue Watch Waterproof Test Tool
$139.99 ($139.99 / Count)
Battery Powered: Yes
Pressure Test Range: 0.3 - 6.0 bar
Dimensions (LxWxH): 9.5 x 5.7 x 10.8 inches
03/07/2024 03:51 pm GMT

How to Use Watch Waterproof Testers

A watch waterproof tester is easy to use and operates by placing the watch in a pressure chamber initially above water. As pressure is added, you can identify seal leaks indicated by air entering the watch. After confirming its integrity above water, the watch can be submerged underwater.

If no bubbles escape, the watch is airtight and the water resistant is intact. Watch waterproof testers will come with individual usage instructions and it is important to follow these instructions for optimal testing.

Watch Waterproof Testers FAQ

The term waterproof means a watch is engineered to withstand exposure to water without allowing it to leak into the case and damage the internal components. Watches are typically rated for water resistance in meters or atmospheres abbreviated to ATM which indicates their ability to resist water pressure at a certain depth.

A watch labeled as 3 ATM waterproof can withstand water pressure equivalent to 30 meters (about 100 feet) underwater. This level of water resistance is suitable for everyday activities like washing hands or light splashes but it’s not intended for prolonged submersion or water-based activities.

A watch that is 10 ATM waterproof means that it can endure water pressure up to 100 meters (approximately 330 feet). This level of water resistance is suitable for swimming, snorkeling and recreational water sports but not for deep-sea diving or high-pressure activities.

Whilst Rolex watches are renowned for their high-quality craftsmanship and water-resistant features, not all Rolex watches are fully waterproof. Many Rolex models are designed with varying levels of water resistance and can be easily identified with water-based names like Oyster and Submariner.

Many Swatch models come with water-resistant features that can handle light splashes, rain and daily activities whilst others are able to withstand greater water depths. Whilst the majority of watches in the range have some level of water resistance, they are not all created equal. Swatch watches come in 3 ATM, 10 ATM and 20 ATM offering a variety of options for different types of usage.

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