A series of large-scale experiments were conducted in the National Institute of Standards and Technology (NIST) Large Fire Laboratory from November 4 to December 10, 2003, to assess the accuracy with which the NIST Fire Dynamics Simulator (FDS) predicts the thermal environment in a burning compartment. In addition, the experiments established a data set to validate prediction of the heat release rate associated with the burning of office furnishings similar in type to those found in the World Trade Center (WTC) towers. The experiments were designed to recreate aspects of the WTC fires including issues associated with limited ventilation, fire spread and growth on real furnishings, and the effects of debris and jet fuel on the heat release rate of fires burning under conditions believed to be similar to those occurring on September 11, 2001. Within a steel-frame compartment (nominally 3 m by 7 m by 4 m high) lined with calcium silicate boards were placed three computer workstations (office modules or workstations) composed of tables, desks, fabric-lined partitions, carpeting, a task chair, paper-filled filing cabinets and bookshelves, as well as a personal computer, keyboard, and monitor. The same configuration of furnishings was used in all experiments except one in which the workstation components were rearranged into component pieces to represent a disrupted non-standard configuration, which may have occurred as aircraft entered the WTC structure. In some of the experiments, several liters of jet fuel were distributed about the workstation components or ceiling tiles within the compartment until a large percentage of the horizontal surfaces of the furnishings were covered. A 2 MW hydrocarbon fire generated by nozzles spraying onto a 1 m by 2 m pan was used to ignite the compartment furnishings. The fuel was a commercial blend of heptane isomers.
Citation: NIST NCSTAR - 1-5
Pub Type: NIST Pubs
World Trade Center, high rise buildings, building collapse, disasters, fire safety, fire investigations, terrorists, terrorism, experiments, compartments, fire behavior, mass loss, heat release rate, gas temperature, carbon monoxide, carbon dioxide, oxygen, vapor phases, thermal environment, combustion, fire models, flame spread