[en] The THERMIR experimental facility at AEE Winfrith was set up in 1975 in order to study on a large scale thermal interactions between molten metals and water. Experiments in THERMIR have used both tin and aluminium as the molten metal and have covered a wide range of temperature conditions, geometry, and triggering arrangements. During these experiments three types of interaction have been observed: coherent interaction of a large mass of metal/water mixture; localized interaction in which a separate drop of metal or a small region of metal/water mixture interacts, producing local expansion but not triggering any interaction of the surrounding materials; incoherent interaction of a large mass of metal/water mixture, in which a sequence of small interactions at different locations is observed to develop in the metal/water mixture. The main aim of recent work has been to observe the propagation stage, and these experiments have confirmed that propagation can be identified with passage of a pressure wave through the mixture. The characteristics of incoherent interactions are discussed and it is suggested that such events could be involved in the escalation of a trigger event into coherent propagation