Movado Group of Canada Inc. The Swatch Group Inc.
Home Company Profile Services Locations Maintenance Tips Contact Us
Water Resistance: The Basics

According to rules set out by the International Standards Organization, water resistant watches should be marked “WATER RESIST” or “WATER RESISTANT” on their back covers. A maximum depth indicator may also appear on the front dial.

Water Resistant watches are grouped into three basic categories:

  • Water resistant for everyday activities (No Dial Markings).
    Watches with this level of water resistance offer only minimal protection from moisture, and are designed to resist perspiration, accidental splashes, rain drops, air-borne dust particles, etc. Watches of this type are generally not designed to withstand complete immersion in water.

  • Water resistant for water related activities (30-100 Meters).
    Watches with this level of water resistance are designed to withstand low to moderate exposure to water, and offer protection during activities such as occasional swimming and skin diving (up to the specified depth). For frequent exposure to water, 100 meter water resistance or better is recommended.

  • Water resistant for diving (150-600 Meters).
    Watches of this type are designed specifically for diving purposes. The case structure of such watches is usually more ridged, allowing it to withstand prolonged exposure to under-water conditions (up to the specified depth).

Other water resistance indicators that may appear on the front dial include:

  • ATM: An abbreviation for atmosphere. One atmosphere is equivalent to 10.33 meters, thus 10ATM = approximately 100 meters.
  • BAR: A unit of air pressure measured in kilograms per square centimeter. 10BAR is the approximate equivalent to 100 meters of water pressure.

Watches without a “WATER RESIST” or “WATER RESISTANT” mark on the back are not water resistant and must be wiped with a dry cloth of high absorbency immediately following exposure to water. If water does penetrate into the interior casing, the watch should be serviced promptly.

Water Resistance: How it is Measured

One of the most precise tests for water resistance does not involve water at all. Instead the watch is placed in a cylinder of compressed air, where the amount of air that enters the watch is measured. Ultra-sensitive equipment then measures the slight drop in pressure in the cylinder (which is proportional to the amount of air that enters the watch).

This test is the basis for the NIHS 92-10 water resistance standard adopted by the Swiss watch industry. A watch is considered water resistant if the rate of leakage into the case does not exceed 0.05 gr of air per minute under a pressure of 2 atmospheres (equivalent to approximately 20 meters of water pressure).

Water Resistance: Proper Care

Water resistance is achieved by placing gaskets between major components of a watch (including the crystal, crown, pushers, and the back). The watch is then tested to the specified depth to ensure a proper seal.

Gaskets are subject to wear-and-tear due to temperature changes, perspiration, dust buildup, etc. These conditions naturally erode the effectiveness of such gaskets and thus the water resistance of the watch.

Opening a water resistant watch may also break its seals (such as during battery replacement). It is therefore recommended that water resistant watches over the 50-meter level be resealed and tested regularly following each battery replacement.

Avoid using solvents, detergents, perfumes, cosmetic products, and/or any other corrosive chemicals on or around the watch. Even if such chemicals are not capable of damaging the casing of the watch, they may have adverse effects on its water resistant seals.