About 11:20 a.m. eastern daylight time on September 15, 2002, westbound Norfolk Southern Railway (NS) train No. 15T derailed in Farragut, Tennessee, while moving at 38 mph. The train was made up of 3 locomotives, 56 loads, and 86 empties; a total of 142 cars with a gross weight of 9,948 tons. Two locomotives and the first 25 cars derailed. A tank car containing sulfuric acid was punctured, releasing a cloud of toxic fumes that prompted local responders to evacuate about 2,600 people from a 4.4-square mile area around the site. The evacuation lasted for about 2 1/2 days. Several local residents were treated for minor respiratory difficulties. There was no fire. Damages were estimated to be $1.02 million.

We determined that the probable cause of the September 15, 2002, derailment of Norfolk Southern train 15T was (1) the decision by the train dispatcher and signal maintainer to allow the train to pass over the spring switch at maximum authorized speed before the switch had been adequately inspected or clamped closed and (2) the lack of company procedures requiring that train dispatchers, after receiving a report of a problem involving a main track switch, immediately stop trains or implement an appropriate speed restriction in the affected area.

​We made recommendations to the Federal Railroad Administration and Norfolk Southern Railway.