(Aπό
http://forums.watchuseek.com/archive/index.php/t-193365.html )
The International Organization for Standardization is the world's largest developer and publisher of International Standards regrouping 157 national standards institutes. ISO has developed over 17,000 International Standards on a variety of subjects and 1,100 new ISO standards are published every year.
ISO Standard number 2281 : "Horology -- Water-resistant watches" defines the essential characteristics of a water-resistant watch (these are not designed for diving, just to withstand an everyday use with short periods of water exposition).
More demanding ISO standard number 6425: "Divers' watches" defines the characteristics of watches suitable for diving. Obviously it implies a set of water resistance measures (to a minimum of 100 metres). Bu it also provides minimum requirements in terms of readability:
• presence of a time-preselecting device such as a unidirectional rotating bezel which shall be protected against inadvertent rotation or wrong manipulation, have a minute scale going up to 60 min, with clear 5-minutes intervals;
• time shall be legible at a distance of 25 cm in the dark;
• indication that the watch is running (usually indicated by a second hand with a luminous tip) ; presence of a battery end-of-life indication in case of a quartz watch.
Further criteria include trials of shock resistance, resistance to attachment etc.
At the end of the day, watches conforming to ISO 6425 are marked with the words DIVER’S WATCH L M (or DIVER'S L M), L indicating the diving depth in metres (usually 100, 200 or 300 M).
You can order the whole set of specifications from the ISO here (
http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=12774)!
