Method of monitoring the loading of a subsea production system

A method of monitoring the condition of a connector between two bodies e.g. umbilicals, jumpers or subsea workover components 100. The method comprises installing the connector 18 to join adjacent bodies 130, 140, 150 and using a connector sensor output and a numerical model to determine a measured force of one or both bodies, the degree of relative body movement or the connector condition. The numerical model is obtained by applying a known magnitude test force to a test element secured to the connector or a test connector, recording the sensor output with the test force applied for a plurality of test forces and using the obtained data to create a numerical model relating the output from the sensor assembly to the force on the test element. The sensors may be strain gauges or pressure sensors which feed a subsea storage 34a. A statistical representation of the model derived from a multivariat analysis may be used in a subsea processor 36a to provide real time failure warning and a full version of the model at the subsea processor or at a topsides processor 36b may provide a long term detailed, e.g. fatigue, analysis.