Overview: Guidebook
Simple to say: The test of the "Standing Good"
When taking out a new insurance policy for sailboats, yacht insurers such as Pantaenius require that the standing rigging has been inspected by a professional service after a certain boat age.
Lightning protection on yachts
Open water is not a favorable place to be during thunderstorms. On a sailing vessel, the mast is often the highest object and lightning will seek out the highest point in its vicinity.