Construction began on Building 6 in 1956. The area where the fire started was constructed in 1967, and a sprinkler system was installed at that time based on the manufacturing being conducted within the building.The first indication of a problem was a water flow alarm which occurred at 06:49:07. This should have instituted a response from GE security; however 2 Derby employees in the building would see the fire and contact MetroSafe. GE security officers would contact MetroSafe eight minutes later.Weather played a role in the incident in several ways. The first responding companies would be tied up on water rescues at other locations, and as a result, the next closest units would respond with a slight delay. At the time of the fire Derby employees were moving product because of water leaking from the roofs, the worse conditions they have ever seen. Later in the incident, when the fire department needed to go off property for water, flooding blocked or delayed their routes in two locations.Because it was Good Friday, there were a reduced number of employees in Building 6, instead of the several hundred who would have been present in the Derby and GE areas. At the same time, General Electric had a single person manning the Boiler House and Mill Water Plant which are located almost a mile apart. Under normal conditions, when an alarm sounds, GE security notifies a patrol officer who checks the location of the alarm. If there is a fire, the patrol officer contacts the security dispatcher who contacts 911. There was a delay in this entire process however some of the delay was offset by Derby employees directly contacting 911. Again, under normal processes, once a fire had been discovered, the Mill Water Plant operator would increase the number of pumps flowing water. A significant delay would occur before the Mill Water Plant operator would drive from the Boiler House to the Mill Water plant and make adjustments. At the time of the incident there were a total of eight pumps that had to be manually started, a system that was installed in the 1950s. Four pumps were down for upgrades. Of the four remaining pumps, three would fail, leaving only one pump working. It was also noted that when the operator arrived at the Mill Water plant, a dump valve was dumping water into a tank instead of closing and allowing some increase in the water pressure. Because of these factors, the water needed by firefighters to extinguish the fire would not be available on property.General Electric has 11-13 Louisville Water Company hydrants that they, GE, are responsible for maintaining. This would have been an additional source of water for firefighters, however the two closest to Building 6 were broken or out of service. A tour of the property as well as observations made by an outside agency revealed that most of the Louisville Water Company hydrants were out of service.An important point of contention is if the 1967 sprinkler system worked as it was designed. At the time of the fire, the use of the building had been switched to the storage of plastics, which required a different more intense rack mounted sprinkler system. General Electric and Derby have a contact in place that spells out the responsibility to make the changes. Thirteen Derby employees did not see any sprinklers at all when they first saw the fire. Another Derby employee saw water flow but said it was not effective. As the last of the Derby employees were exiting the building, two General Electric security officers entered, one saw sprinklers above the fire, one was not sure. Others saw sprinklers flowing on other systems in other areas of the building. Whatever was flowing had very little pressure. An additional indicator as to the performance of the sprinkler system was the exterior wall mounted sprinkler gongs. While they were inspected and found in good condition one year ago, none of them sounded which indicates water was not flowing to the sprinklers.During inspections of the sprinkler systems in 2013 and 2014, General Electric was notified that the hazards were not adequately protected (2013) and in both years that the system need to be reevaluated based on the use of the building. Regarding the cause of the fire, careless smoking, Metal Halide light fixture failure and an intentional set fire were discounted as causes of this incident. While scientific data did not plot a lightning strike directly to Building 6, there were several other strikes in Appliance Park. A very credible witness identified a location of a strike, directly above where the fire started. During the 24 hours prior to the fire there was a significant amount of rain on the property, which necessitated Derby moving product because of leaks in the roof. The possibility of rain leaking into electrical components, causing a short, cannot be eliminated. As a result, under the strict guidelines of NFPA 921, the cause will be undetermined. The total loss for General Electric is greater than 50 million dollars and the loss for Derby Industries is 50 to 60 million dollars.