FAQ Watches

A certified chronometer is a movement that has passed seven specific tests for accuracy and quality by an independent body, in Switzerland typically the Controle Officiel Suisse des Chronometeres, or COSC. Mechanical movements are tested in 5 different positions at temperatures from 8 to 38 degrees Celsius and over 15 days. To receive certification, a movement must run within - 4 to + 6 seconds per day over 10 days, vary no more than 2 – 5 seconds in different positions and no more than 10 seconds from the mean daily test-rate.

A watch may perform differently depending on the person who wears it and the person’s habits. Different life-styles will have different effects on watches and may not necessarily mirror a laboratory’s “ideal” testing conditions. Other reasons why chronometers may run inaccurately are that tests are performed on movements, not on watches. During encasing, small strains can cause changes to the accuracy of a movement. Also, lubricants used in watches dry out and rubber or nylon gaskets deteriorate. Sooner or later, different properties and functions of a watch may be affectd, and it is normal, indeed necessary, that an overhaul be performed on a watch from time to time.

Watches are built to withstand water pressure up to specified depths and are tested in laboratory conditions to confirm that they are water-resistant. The 3 most common measures for water pressure are ATM, depth in meters, and Bar. 1 ATM is 1.013 BAR, or 1013 Millibar, and is equivalent to the mean air-pressure at the earth’s surface (sea level); it is also the pressure of water at a depth of 10 m. The deeper, the higher the pressure: 2 ATM is the water pressure at 20 m, 5 ATM at 50 m, 20 ATM at 100 m, and so on. Normal watches are certified water-resistant to 2 ATM or 3 ATM, which should suffice for normal contact with water and surface swimming. Divers watches have to be water-resistant to greater depths, at least 10 ATM (100 m), but typically in modern watches 30 ATM (300 m). Top diving watches are built to withstand 100 ATM, the pressure of water at 1000 meters.

Deep dives, in particular to depths of over 50 m, are interrupted by breaks the divers take in underwater bells that are filled with highly pressurized gas, a mixture of Oxygen and Helium. As Helium molecules are smaller than water or Oxygen molecules they seep into normally water and air-tight containers and instruments, e.g. diving watches. When divers resurface after dives with multiple sorties at big depths, not only do they need to decompress at various levels, but the Helium that has accumulated in their instruments or water-tight containers needs to be released, otherwise the expanding gas would cause the containers to burst. One-way Helium valves are mounted into these deep-dive instruments to allow the release of Helium molecules during resurfacing and decompression.

CITES is the Convention on International Trade in Endangered Species of Wild Fauna and Flora. It is an international agreement between governments and aims to ensure that international trade in specimens of wild animals and plants does not threaten the survival of such plants and animals. More than 30,000 species, whether traded as live specimens, fur coats, leathers or dried herbs, are accorded varying degrees of protection.

Watch industry products which are subject to mandatory CITES certification are primarily alligator straps. CITES certificates are obtained when products from animals that are on the endangered species list originate from approved farms or other legal sources.

CITES requires that the final buyer’s name is reported back to the authorities that enforce the CITES regulations, in Thailand the Royal Forestry Department. This aims not only achive compliance but also to foster broad awareness and responsibility about the nature and origin of products consumed, also among end consumers.

PVD stands for Physical Vapour Deposition process. This is a highly durable industrial process that deposits molecules that form a hard ceramic coating with an attractive looking color on a steel or other metal base. Colors may be black, white, brown, gold, blue or other hues. This process is extensively used in the watch industry for decorative purposes. PVD, however, is also a process used in industrial tooling to improve durability, temperature and oxydation resistance, and other wear protection.