The analysis of instantaneous pressure fluctuations is utilised in a cold modelling study of a pilot scale fluidised bed catalytic reactor for ethane oxychlorination. It is demonstrated that the fluid dynamic behaviour of a cold model of this tine particle (Geldart group A) system is well characterised by the frequency spectrum, the standard deviation and the cross-correlation of pressure signals detected at different locations within the bed and in the freeboard. The influence of operating parameters, such as gas flow rate, initial bed height, reactor configuration (internals) and average value of the local pressure, is investigated, and a comparison is made with the features exhibited by Geldart group B systems (fluidised bed combustors) for which the same diagnostic techniques have been applied. Finally, the applicability to fine particle suspensions of literature correlations for dominant frequency and propagation velocity of pressure waves is discussed with reference to the combined influence of the eruption of many small bubbles at the bed surface, and the compressibility of the gas contained within the particle-bed interstices.