A diving watch, also commonly referred to as a diver's or dive watch, is a watch designed for underwater diving that features, as a minimum, a water resistance greater than 1.1 MPa (11 atm), the equivalent of 100 m (330 ft). The typical diver's watch will have a water resistance of around 200 to 300 m, though modern technology allows the creation of diving watches that can go much deeper. A true contemporary diver's watch is in accordance with the ISO 6425 standard, which defines test standards and features for watches suitable for diving with underwater breathing apparatus in depths of 100 m (330 ft) or more. Watches conforming to ISO 6425 are marked with the word DIVER'S to distinguish ISO 6425 conformant diving watches from watches that might not be suitable for actual scuba diving.
Breitling Avenger Seawolf, with a water resistance of 3,000 m (10,000 ft). The round feature on the watch case side at 9 o'clock is an integrated helium release valve.
The vintage 1936 California Dial Radiomir Panerai
The Blancpain Fifty Fathoms model fami;y was introduced in the mid 1950s
US Marine diver with a diving watch and an analog depth gauge
Water Resistant is a common mark stamped on the back of wrist watches to indicate how well a watch is sealed against the ingress of water. It is usually accompanied by an indication of the static test pressure that a sample of newly manufactured watches were exposed to in a leakage test. The test pressure can be indicated either directly in units of pressure such as bar, atmospheres, or as an equivalent water depth in metres.
WATER RESISTANT marking on the back of a Victorinox wristwatch
ISO 6425 compliant DIVER'S 200M marked diving watch
Integrated helium release valve releasing breathing gas from the watch case. This feature is found in some mixed-gas diving watches to prevent the crystal from popping off during decompression.