Testing scope is watch-specific
Professional assessment may include dry and/or wet methods and targeted seal work, depending on the watch, its condition, age, construction, intended use, and approved estimate. Not every watch is wet-tested or tested to its original depth rating. A test result does not make water resistance permanent and is not a recertification, waterproof guarantee, or future-performance warranty unless the written repair scope and final report expressly say so.
How Professional Water-Resistance Testing Works
An original depth rating does not by itself describe a watch's present condition. Age, opening, impact, service history, seals, and current manufacturer instructions affect whether and how an individual watch should be tested.
Professional testing can document an individual watch's response at the stated method and level at that time; it does not prove a watch is universally dry or create permanent water resistance. Use “recertification” only when the written scope and final report expressly document it.
1. The Vacuum (Dry) Test
Before a watch ever touches water, it goes into a pressure chamber. The machine measures the case's expansion to a fraction of a millimeter.
2. The Pressure (Wet) Test
For eligible watches and approved scopes, a watchmaker may select an appropriate wet or dry method. Not every watch is suitable for a wet test or for testing to its original rating.
- The Logic: This mimics the actual weight of the ocean at specific depths (e.g., 10 ATM or 100 meters).
- The Condensation Check: After the pressure is released, the watch is placed on a heating element and a cold drop of water is placed on the crystal. If fog forms inside, you have a leak.
Why Present-Condition Testing Matters
Most owners assume that if they don't open the watch, the water resistance remains intact. Unfortunately, gaskets are organic materials—usually rubber or Teflon—and they have enemies:
- UV Rays & Heat: Constant sun exposure dries out gaskets, making them brittle.
- Chemicals: Chlorine from pools and even salt from the ocean can degrade the seals over time.
- Soap: Taking a hot shower with your watch is often worse than a 10-meter dive. Soap reduces the surface tension of water, allowing it to slip past aging gaskets more easily.
Representative Repair Cases
Explore selected repairs from the Gray & Sons archive. A watch is evaluated individually, so the work required for another timepiece may differ.
Related Watch Repair Guides
Request a Watch Repair Evaluation
A repair request begins with an individual inspection and estimate. Send your watch securely or visit Gray & Sons in Surfside, Florida, to discuss the next step.