There were 90 employees in the facility at the time of the fire, which began when a deep fat fryer vat developed a hydraulic leak, which subsequently caught fire at around 8:30 AM. This cooker's temperature was controlled by thermostat and was maintained at a constant , which was variable by design to either way. The fire spread rapidly, causing a panic so that some workers suffered trauma injuries during a rush to escape. Large quantities of smoke were produced by a combination of burning soybean oil and chicken, and melting roof insulation. The smoke was later found to be hydrocarbon-charged and had the potential to disable someone within a few breaths. Several gas lines embedded in the ceiling also caught fire and exploded.