Failure of standing rigging on yachts is not an uncommon phenomenon, often occurring without any prior warning, and can be due to faults within the terminals which are not visually detectable.

The N.D.T. method, which uses a Digital Micro Ohmmeter, measures the small electrical resistance within the rigging terminals.  Results are then compared with a standard scale of resistances for the corresponding sized terminals.  Readings which are above 10% of this scale indicate defective fittings:-

THE TEST WILL IDENTIFY THE FOLLOWING:-

Internal corrosion
Broken strands
Cracked terminals
Movement inside terminals
Defective swaging

Better safe than sorry:-  if a non-destructive rig test indicates the advisability of replacing a set of standing rigging, or even just one stay, this has to be infinitely less costly than the risk of a complete loss of a mast or rig at sea, with all its accompanying horrors.

The Digital Micro Ohmmeter has been used in the electrical power industry for many years and has now been adapted for use in the marine environment.  It is stressed that the N.D.T. only indicated any change of state of specimens tested and is the only N.D.T. available for detecting terminal faults.