Diving watch
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, the equivalent of. The typical diver's watch will have a water resistance of around, 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 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.
To a large extent the diver's watch has been superseded by the personal dive computer, which provides an automatically initiated dive timer function along with real-time decompression computation and other functions.
History
The history of efforts to use watches underwater and to make watches that are water resistant, or waterproof and to make dive watches goes back to perhaps the 17th century. In the 19th century water and dust resistant watches were usually one-off pieces custom made for a particular customer and described as "Explorer's Watches". Hard hat divers of that period sometimes placed common pocketwatches on the inside of their helmets in order to know the time spent under water. Early in the 20th century such watches were industrially produced for military and commercial distribution. Like their predecessors early 20th century dive watches were developed in response to meet the needs of several different but related groups: explorers, navies, and professional divers.In 1926, Rolex bought the patent for the “Oyster” watch case, featuring a hermetic seal. On 7 October 1927 an English swimmer, Mercedes Gleitze attempted to cross the English Channel with a new Rolex Oyster hanging round her neck by a ribbon on this swim. After more than 10 hours in the chilly water the watch remained sealed and kept good time throughout.
Omega SA is credited as the creator of the world's first industrially produced diving watch intended for commercial distribution, the rectangular Omega "Marine" with a patented double sliding and removable case, introduced in 1932. After a series of trials undertaken by the Swiss Laboratory for Horology in Neuchâtel in May 1937, the watch was certified as being able to withstand a pressure of, equivalent to a depth of, without any water intake whatsoever.
Following a request made by the Royal Italian Navy, in September 1935, for a luminous underwater watch for divers, Panerai offered "Radiomir" underwater timepieces in 1936. These watches were made by Rolex for Panerai.
In addition, a large number of "canteen" style dive watches by Hamilton, Elgin or Waltham were made to military specification during and after World War II. However, these watches were made in small numbers, and were not intended for large-scale commercial distribution. Today, interest in these watches is limited to collectors.
Various models were issued by Blancpain in small quantities to the military in several countries, including US and French Navy combat diver teams. The Fifty Fathoms was worn by Jacques Cousteau and his divers during the underwater film "Le monde du silence", which won the Palme d'Or at the Cannes film festival in 1956, and in the US when TV star Lloyd Bridges wore a Blancpain Fifty Fathoms dive watch in a photo that appeared on the cover of the February 1962 edition of Skin Diver Magazine.
Zodiac debuted their Sea Wolf line of waterproof watches at the 1953 Basel Fair as well.
The Rolex Submariner, the first modern dive watch, was introduced at the Basel Watch Fair in 1954. This coincided with the development of self-contained underwater breathing apparatus, known as scuba. In 1959, the United States Navy Experimental Diving Unit evaluated five diving watches that included the Bulova US Navy Submersible Wrist Watch, Enicar Sherpa Diver 600, Enicar Seapearl 600, Blancpain Fifty Fathoms, and the Rolex Oyster Perpetual.
In 1961, Edox launched the Delfin line of watches, with industry-first double case backs for water resistance to 200 meters. They later released the Hydrosub line in 1963 featuring the first crown system with tension ring allowing depths of 500 meters.
In 1961, Rolex began to include a skindiver handbook with the Submariner, then available in two models, one water resistant to, the other, less expensive version, to. It was the choice of watch for the character of 007 in the first ten James Bond films, causing the "Sub" to achieve an iconic status.
In 1964, Zuccolo Rochet & Cie issued the Grands Fonds 300 to Explosive Ordnance Disposal units using a mechanical operation as electric interference could trigger off explosions. It used an easy clean system that allows freshwater to free up residue between the watch case/bezel. Another notable function is the crown placed in the lower watchstrap to prevent snagging on objects during underwater operations.
The Tornek-Rayville TR-900 issued to the US Navy used tritium, later promethium on the dials and a moisture intrusion indicator, which changed color if water penetrated the watchcase. However, only 1000 existed as most of these watches were destroyed by the Navy upon their return due to strict hazardous waste disposal rules for equipment containing radioactive material.
In 1965, Seiko put the 62MAS on the market, the first Japanese professional diver watch.
During the 1960s, commercial work in the oceans and seas created professional diving organisations that needed more robust watches designed for diving operations at greater depths. This led to the development of the first 'ultra water resistant' watches like the Rolex Sea-Dweller 2000, that became available in 1967, and was produced in several variations, and the Omega Seamaster Professional 600m/2000 ft, also known as the "", that became available in 1970, and was produced in several variations.
In 1983, the US Navy Experimental Diving Unit evaluated several digital watches for use by US Navy divers.
In 1996, the International Organization for Standardization introduced the standards and features for diving watches regulated by the ISO 6425 – Divers' watches international standard.
Many contemporary sports watches owe their design to diving watches.
The vast majority of divers now use electronic, wrist-worn dive computers. A dive computer or decompression meter is a device used by a scuba diver to measure the time and depth of a dive so that a safe ascent profile can be calculated and displayed so that the diver can avoid decompression sickness. Diving watches and depth gauges are still fairly commonly used by divers as backup instruments in case of dive computer malfunctions, although it is becoming more common to carry a backup dive computer with full decompression functionality for dives with significant planned decompression, as it is a safer option.
Characteristics
Many companies offer highly functional diving watches. Whilst diving watches are primarily tool watches, some companies offer models that can in addition to this be regarded by some as jewellery or fine mechanical devices. Diving watches can be analog or digital. Besides pure analog and digital models some diving watch models combine digital and analog elements.ISO 6425 standard for diving watches
The standards and features for diver's watches are regulated by the International Organization for Standardization in the ISO 6425 standard; German Industrial Norm DIN 8306 is an equivalent standard. Besides water resistance standards to a minimum of 100 m depth rating ISO 6425 also provides minimum requirements for mechanical diver's watches such as:- Equipped with a diving time indicator. This device shall allow the reading of the diving time with a resolution of 1 min or better over at least 60 min.
- The presence of clearly distinguishable minute markings on the watch face.
- Adequate readability/visibility at in total darkness.
- The presence of an indication that the watch is running in total darkness. This is usually indicated by a running second hand with a luminous tip or tail.
- Magnetic resistance. This is tested by 3 exposures to a direct current magnetic field of 4,800 A/m. The watch must keep its accuracy to ± 30 seconds/day as measured before the test despite the magnetic field.
- Shock resistance. This is tested by two shocks. The shock is usually delivered by a hard plastic hammer mounted as a pendulum, so as to deliver a measured amount of energy, specifically, a 3 kg hammer with an impact velocity of 4.43 m/s. The change in rate allowed is ± 60 seconds/day.
- Chemical resistance. This is tested by immersion in a 30 g/L NaCl solution for 24 hours to test its rust resistance. This test water solution has a salinity comparable to normal seawater.
- Strap/band solidity. This is tested by applying a force of 200 N to each spring bar in opposite directions with no damage to the watch or attachment point.
- The presence of an End Of Life indicator on battery powered watches.
Watch case
The watch cases of diving watches must be adequately water resistant and be able to endure the galvanic corrosiveness of seawater, so the cases are generally made out of materials like grade 316L or 904L austenitic stainless steel and other steel alloys with higher Pitting Resistance Equivalent factors, titanium, ceramics and synthetic resins or plastics. If metal bracelets are used they should be made of the same metal alloy as the watch case to prevent corrosion of the metal with the lower PRE-factor as it will act as a sacrificial anode. The case must also provide an adequate degree of protection against external magnetic influences and shocks, though diver's watches do not have to be able to endure strong magnetic fields and shocks. To make mechanical watch movements themselves shock resistant various shock protection systems can be used.The cases of diving watches have to be constructed more stoutly than typical dress watches, because of the requirements necessary to withstand a seawater environment at depth. As a consequence diving watches are relatively heavy and large compared to dress watches made out of similar materials. Under water sheer weight is of less consequence than buoyancy, which a diver can address by a buoyancy compensator vest. Before the introduction of other case materials diving watch cases were made of stainless steel. Stainless steel is however still often used as case material in contemporary diving watches.