An inspection system for the analysis of a conduit and the material surrounding said conduit, the system comprising: a first apparatus configured for insertion into said conduit and comprising: transmission means for transmitting a varying primary magnetic field inducing an electromagnetic response thereto in the form of a decaying secondary magnetic field; detection means for detecting and measuring said electromagnetic response; conversion means for converting said electromagnetic response to a discrete signal; and communication means for reading and communicating said discrete signal to a second apparatus positioned remotely to the first apparatus; said second apparatus comprising: storage means for storing said discrete signal; processor for processing said discrete signal; and a display for displaying said processed discrete signal; the system being characterised by: the secondary magnetic field being influenced by both the conduit and the material surrounding the conduit; the first apparatus further comprising processor controlling said transmission means, and said detection means, and said conversion means for sampling the detected secondary magnetic field to sample the detected secondary magnetic field in a plurality of discrete intervals to measure the exponential decay in amplitude of the secondary magnetic field, and controlling said communication means to communicate said discrete signal to the second apparatus; and the processor of the second apparatus processing the sampled data to perform a time domain analysis of the data based on the measured decay in amplitude of the secondary magnetic field to determine the state of the conduit and material surrounding the conduit. a first apparatus configured for insertion into said conduit and comprising: transmission means for transmitting a varying primary magnetic field inducing an electromagnetic response thereto in the form of a decaying secondary magnetic field; detection means for detecting and measuring said electromagnetic response; conversion means for converting said electromagnetic response to a discrete signal; and transmission means for transmitting a varying primary magnetic field inducing an electromagnetic response thereto in the form of a decaying secondary magnetic field; detection means for detecting and measuring said electromagnetic response; conversion means for converting said electromagnetic response to a discrete signal; and communication means for reading and communicating said discrete signal to a second apparatus positioned remotely to the first apparatus; said second apparatus comprising: storage means for storing said discrete signal; processor for processing said discrete signal; and a display for displaying said processed discrete signal; the system being characterised by: the secondary magnetic field being influenced by both the conduit and the material surrounding the conduit; the first apparatus further comprising processor controlling said transmission means, and said detection means, and said conversion means for sampling the detected secondary magnetic field to sample the detected secondary magnetic field in a plurality of discrete intervals to measure the exponential decay in amplitude of the secondary magnetic field, and controlling said communication means to communicate said discrete signal to the second apparatus; and the processor of the second apparatus processing the sampled data to perform a time domain analysis of the data based on the measured decay in amplitude of the secondary magnetic field to determine the state of the conduit and material surrounding the conduit. storage means for storing said discrete signal; processor for processing said discrete signal; and a display for displaying said processed discrete signal; the secondary magnetic field being influenced by both the conduit and the material surrounding the conduit; the first apparatus further comprising processor controlling said transmission means, and said detection means, and said conversion means for sampling the detected secondary magnetic field to sample the detected secondary magnetic field in a plurality of discrete intervals to measure the exponential decay in amplitude of the secondary magnetic field, and controlling said communication means to communicate said discrete signal to the second apparatus; and the processor of the second apparatus processing the sampled data to perform a time domain analysis of the data based on the measured decay in amplitude of the secondary magnetic field to determine the state of the conduit and material surrounding the conduit.