This video comes to you from Yachting Monthly.  It is a crucial video to watch regardless of what level sailing experience you have.  This is a controlled experiment and you can see how dangerous it can be and how much work it is to remedy the aftermath.  How old is your standing rigging?  Manufacturers of 316 stainless steel recommend replacement at 10 years maximum, 7 years by the US Coast Guard if you are planning to charter your boat. Visually inspecting your rigging is fine, however most problems occur INSIDE fittings out of sight and failures occur without warning! 

New standing rigging installed w/mast up-Bahia 46 & Leopard 45-San Pedro, Belize