Distributed sensing for liquid leaks and spills

This paper describes a very simple generic approach to detecting leaks and spills using fibre optic sensing technologies. The system has been configured for distributed sensing and the sensitive fibre cable can detect one, or several wet section(s) one metre in length over distances extending to 10km with location accuracies of the order of 1 metre. Furthermore, by modifying the interface chemistry, the system will respond to either aqueous solutions or to hydrocarbon fluid with no cross talk from one to the other. The system also responds in time scales of seconds, and is reversible over - to date - indefinite number of cycles. The system can also be configured to respond to water or (some) hydrocarbon vapours, predominantly at high vapour pressures. Finally, much simplified shorter range versions of the sensors are currently being investigated with a view to detecting the occurrence of a leak or spill at any point in the path length of metres or tens thereof.