A set of procedures, knowliedge which is meant to guarante the physical integrity of the sailors. They include, usually, maintenance of minimum on board equipment; the practice of navigation handling procedures, in case of bad wheather, capsizing, dent, collision etc; the knowledge of things which come before the need to perform those procedures, such as those that refer to meteorology and weather forecast; the capacity to determine your own situation, through the use of charts, knowledge about astronomic navigation etc; the communication, by means of optical and visual signs and the use of radiotelegraphic gadgets. Those measures are recommended or, simply, spread by international authorities - usually based on worldwide rules, such as the International Convention for the Safety of Life at Sea - or by international sports corporations.