Watch seal test - The difference between a protected watch and a watch damaged by moisture

Everything you need to know about watch water resistance testing - when to do it, how it works, and why it's crucial for mechanism protection

Watch Water Resistance Testing - Why it's Important, How it's Done, and What You Need to Know

Modern wristwatches are much more than a fashion accessory. Some are designed for daily use, others for sports, and even for professional diving. One of their key distinguishing features is water resistance - a characteristic that ensures the watch is protected from the ingress of liquids, moisture, and dust.

However, water resistance is not a permanent feature but a condition that needs to be checked and maintained. This is where watch water resistance testing comes in - a professional procedure that ensures the watch continues to meet manufacturer standards even after use and various repairs.

In this article, we will detail what water resistance is, why it's important, how water resistance testing is performed, when it should be done, and the risks of neglecting it.

What is water resistance for a watch?

Water resistance is a watch's ability to prevent water, moisture, dust, and tiny particles from entering its internal mechanism.

Water resistance is achieved through:

Gaskets (special rubber seals) on the watch back, push-buttons, and crown.

Precise connection of the watch glass to the bezel.

Quality sealing of the watch back with pressure or screw-down.

Over time, gaskets wear out, dry up, or lose their flexibility, which is why periodic inspection is required.

Why is water resistance testing important?

1. Protection of the mechanism - A watch mechanism, especially for luxury or automatic watches, is very sensitive to liquid ingress. Water or moisture can disrupt its operation and even destroy the watch.

2. Maintaining water resistance - Manufacturers specify different levels of water resistance: 3ATM, 5ATM, 10ATM, and even more. Without testing, it's impossible to know if the watch still meets this requirement.

3. Preventing rust - Water ingress can cause corrosion in the mechanism and irreversible damage.

4. Maintaining watch value - A luxury watch that receives proper care retains its value over time.

5. Safety - For divers, a watch that is not water-resistant can be not only a financial matter but also a matter of safety.

When is it recommended to perform water resistance testing?

After any opening of the watch back - for example, when replacing a watch battery. Any opening compromises the original seal.

Before serious water exposure - if you plan to dive, swim in the sea or a pool.

Once every one to two years - as a general recommendation, even if you haven't opened the watch.

After a strong blow or fall - Physical impact can loosen gaskets and damage the glass.

When the watch is old - Watches 5-10 years old tend to lose natural water resistance due to drying of the gaskets.

How is watch water resistance testing performed?

Water resistance tests are performed using specialized pressure testing devices:

1. Dry Test

The watch is placed in a sealed device that applies air pressure to it.

Sensors check if the watch back slightly deforms - which indicates air ingress/lack of sealing.

This is a quick, accurate, and safe test that does not endanger the watch.

2. Wet Test

The watch is placed in a pressure chamber containing water.

Air pressure is applied, and bubbles are checked for ingress.

This method is less common today due to the risk of actual water ingress.

3. Combined Test

In professional laboratories, a dry pressure test is performed first, and only if there is doubt - a wet test is combined.

Watch Water Resistance Levels - What Do They Mean?

The marking on the watch back indicates the water resistance level, but many are confused:

3ATM / 30 meters - Resistance to splashes and hand washing in cold/lukewarm water only.

5ATM / 50 meters - Suitable for light swimming.

10ATM / 100 meters - Suitable for swimming and shallow diving.

20ATM and above - Suitable for professional diving.

It's important to understand: “30 meters” does not mean you can actually dive to 30 meters. This is a comparison to static pressure and not to real-life swimming or diving.

Common Mistakes to Avoid

1. Assuming the watch is sealed forever - Water resistance wears out over time.

2. Battery replacement without testing - Every opening of the back requires a pressure test.

3. Improper use of a water-resistant watch - Operating buttons underwater can damage the seal.

4. Ignoring condensation in the glass - The appearance of fog indicates moisture ingress and requires immediate referral to a laboratory.

Who performs water resistance testing?

Water resistance tests are performed in professional watch repair laboratories, equipped with advanced pressure testing devices.

Not every store offers the service, so it is recommended to ensure that the place you go to uses appropriate equipment and also provides a guarantee on the result.

How much does a watch water resistance test cost?

The price varies depending on the type of watch and the level of testing:

Basic testing after battery replacement - not included in the price and can be obtained for a small additional fee.

Professional testing in a laboratory - which takes several days, costs around 100-150 NIS, and sometimes more for luxury and diving watches.

Testing combined with gasket replacement - the price may reach 200-300 NIS.

Frequently Asked Questions about Watch Water Resistance Testing

Does every watch require water resistance testing?

No. Only watches designated as water-resistant. However, even a watch not so designated may benefit from basic protection against moisture if the seal is maintained.

Is water resistance testing included in battery replacement?

Not always. If the watchmaker is professional - they will recommend testing, but it is an additional service not automatically included in the battery price.

What happens if a watch fails a water resistance test?

In such a case, gasket replacement, glass repair, or other professional treatment is required to restore its resistance.

How often should water resistance be checked?

The recommendation is once every one to two years, and certainly after every back opening or serious water exposure.

Does testing damage the watch?

No. Dry testing does not cause any damage. Wet testing is performed only when necessary and with great care.

Summary

Watch water resistance testing is not a luxury, but an integral part of proper maintenance. A water-resistant watch does not remain so forever - gaskets wear out, glass may loosen, and every back opening changes the water resistance level.

Professional testing ensures that your watch will continue to maintain its resistance, protect its internal mechanism, and accompany you for many years.

At MASTER TIME, you will find not only original brand watches but also a professional watch repair laboratory, where you can perform battery replacement, mechanism repairs, and water resistance testing - so your watch continues to work accurately and reliably.