Abstract Industrial fires originating in cable arrays are not common, but when they do occur, they can result in economic losses that far exceed the physical damage caused by the fire. This is particularly true for fires in telecommunication systems, where Central Offices necessarily contain enormous arrays of cables which are supported in multiple levels of elevated cable trays that are distributed throughout the facility. The insulation and protective covers of most cables are combustible and the surface to volume ratio of the fuel array is typical of close packed cribs. In this paper, an analysis is presented that was developed to describe fire growth that occurred in a Telecommunication Central Office fire, initiating at an intersection of cable trays in the toll terminal area. Though the building contained a complete fire detection system, the time between the first recorded fire alarm and notification of the local fire department was extensively delayed because of weather problems and misinterpreted signals. The building was not sprinkler protected. Consequently, the fire persisted for an extensive period of time. The heaviest fire damage involved an area of only 110 m 2 , but because of the local cable density in this area, the smoke and combustion gases caused potentially irreversible damage to telephone systems throughout the floor of origin. The analysis developed here uses available test data on cable burning in a simplified model of fire development to predict the characteristics of the actual fire. These characteristics include: fuel burning and heat release rates, smoke and HCL generation, growth of the smoke layer, smoke and HCL concentration in the layer, smoke detector activation and sprinkler actuation. The results of the analysis are then used to estimate how alternate countermeasures could have effected the outcome of the initiating fire. This simple, empirically driven analytical model is sensitive to local conditions, fuel geometry and fuel composition.