Water-resistance is one of the most common properties of watches, which is found in models of all price categories, differing in style and designed for different situations. What is this water resistant watch meaning, how to correctly understand it, and what does it depend on?
Water resistant watch meaning
Water resistant watch meaning is tightness. The water that gets into the mechanism, especially the salty water, negatively affects its operation up to breakdowns and irreversible damage to its parts. O-rings and gaskets at the points of fastening of the bezel, glass, back cover, and the connection of the crown and buttons with the case are responsible for achieving tightness.
What affects water resistance and tightness?
The main factors are pressure and air/water temperature. They affect the characteristics of the sealing materials, changing their properties so that the tightness is reduced.
Types of marking
WR – an abbreviation for water-resistant, the abbreviation is put together with a figure indicating how many meters it is theoretically possible to submerge a watch underwater without harm to them. For example, WR30, WR50, and so on.
Bar or atm – the number of atmospheres, where 1 atmosphere = 10 meters. For example, 3bar / 3atm = 30 meters.
M, meters – meters, where the figure is equal to the number of meters that can be immersed. For example, 30m, 50m, 100m and so on.
Certified diving watches are often labeled diver’s watch.
The first sign that the watch is not tight and leaked: Condensation appears on the inside of the glass. If a small amount of moisture gets in, the watch can be saved by disassembling and drying it. Do this only in specialized service centers. If saltwater gets inside, the forecasts are not so comforting – the mechanism may be damaged without the possibility of recovery.
The International Organization for Standardization (ISO) has developed two standards for assessing the water-resistance of watches. ISO 6425 applies to professional diving models, the criteria of ISO 22810 apply to all other watches.
Professional diving watch
The international standard ISO 6425 spells out specific parameters that a waterproof watch must meet and the criteria for checking them.
Each instance is immersed to a depth, tested under pressure, subjected to a sharp change in temperature, and checked under conditions of condensation. All tests take place underwater in conditions as close to real as possible. For example, the water is salty, like in the sea and ocean.
Other waterproof watches
The ISO 22810 standard is much less strict and does not mean specific immersion depths of watches with the corresponding marking, but the conditions in which they can be operated. Therefore, the instructions for such watches have tables of acceptable actions: rain, washing, showering, swimming in the pool, diving with a snorkel and scuba diving, and so on. The actual level of depth at which the watch will continue to operate without passing water is, for the most part, left to the discretion of the manufacturer.
By the way:
The water resistance level of “ordinary” watches does not always mean that you can immerse in them at 30, 50, or 100 meters.
The fact is that during testing in the laboratory, static pressure acts on the watch, and in real conditions, it is dynamic, and it sometimes exceeds the first one by several times.
Specialized models for diving, including diving watches. It can work even at deeper depths than the manufacturer guarantees.
Unlike ISO 6425, not all batch copies are tested according to ISO 22810 but randomly selected. The pressure resistance test can be carried out in an air chamber (and not underwater), and the minimum test duration is only 10 minutes. The impact of the shock load is much less severe (or absent altogether), tests in saltwater are not carried out.