Callidus Design has been appointed by FMC Technologies to carry out the design of a cooling system for their new hyperbaric test chamber at their facility in Bellshill, Lanarkshire. The chamber will be used for testing numerous types of equipment which are intended to operate on the sea bed. The chamber simulates the environmental conditions of pressure and temperature which the component is likely to experience in that location. During the testing process the equipment produces heat and if this is not removed then the chamber temperature will rise and the conditions will no longer represent those at the sea bed. Therefore, the challenge is to design a cooling system to maintain the chamber temperature at normal sea-bed conditions. Traditional heat exchange surfaces will be of no use at operating pressures in excess of 400Bar and therefore a bespoke heat exchanger will require to be designed from first principles.