National Transportation Safety Board
Office of Public Affairs
WASHINGTON, D.C. - The National Transportation Safety Board today determined that the crew of a Norfolk Southern train failed to return a main line switch to the normal position after the crew completed work at an industry track in Graniteville, South Carolina early this year.
On January 6, 2005, a northbound Norfolk Southern Railway Company (NS) freight train 192 encountered an improperly lined switch that diverted the train from the main line onto an industry track where it struck an unoccupied, parked train P 22. The collision derailed both locomotives and 16 of the 42 freight cars of train 192 as well as the locomotive and 1 of 2 cars of train P22. Among the derailed cars from train 192 were three tank cars containing chlorine, one of which was breached, releasing chlorine gas. The train engineer and eight other people died as a result of chlorine gas inhalation. About 5,400 people within a 1- mile radius of the derailment site were evacuated for several days, many of them complaining of respiratory difficulties.
"This was a tragic chain of events that did not have to happen and unfortunately resulted in the loss of life," said NTSB Acting Chairman Mark Rosenker. "The Board can not stress enough the importance of following proper procedures and protocols, at all times, when operating these massive machines."
The Board determined that the crew of train P22 failed to reline a switch back to the mainline after using it, leading to the subsequent and unexpected diversion of train 192 into an industry track where it struck train P22 and derailed. The Board also concluded that had the conductor of train P22 held a comprehensive job briefing at the industry track, as required by NS operating rules, the crew may have attended to the main line switch, and the accident may not have occurred.
Contributing to the accident was the absence of any feature or mechanism that would have reminded crewmembers of the switch position and thus would have prompted them to complete this final critical task before departing the work site. Postaccident inspection revealed that the switch was lined and locked for the industry track, as it had been when train P22 used the switch on the evening prior to the accident. Investigators noted that there was no evidence of tampering and no other trains used the track in the area from the time the P22 crew left until the accident the next morning.
The Board stated that contributing to the severity of the accident was the puncture of the ninth car, a tank car containing chlorine, which resulted in the release of poisonous chlorine gas. The chlorine gas release that occurred in this accident resulted when the shell of the ninth car on the train was punctured by the coupler (mechanism that joins rail cars) of the 11th car. Metallurgical examination of the damage on the shell around the puncture documented several impression marks on the shell that matched damage found on projecting surfaces of the coupler. Consequently, the Safety Board concluded that the chlorine gas release occurred when the coupler of the 11th car punctured the shell of the ninth car.
As a result of this accident, the Safety Board made the following safety recommendations to the Federal Railroad Administration:
- Require that, along main lines in non-signaled territory, railroads install an automatically activated device, independent of the switch banner, that will, visually or electronically, compellingly capture the attention of employees involved with switch operations and clearly convey the status of the switch both in daylight and in darkness;
- Require railroads, in non-signaled territory and in the absence of switch position indicator lights or other automated systems that provide train crews with advance notice of switch positions, to operate those trains at speeds that will allow them to be safely stopped in advance of misaligned switches;
- Require railroads to implement operating measures, such as positioning tank cars toward the rear of trains and reducing speeds through populated areas, to minimize impact forces from accidents and reduce the vulnerability of tank cars transporting chlorine, anhydrous ammonia, and other liquefied gases designated as poisonous by inhalation;
- Determine the most effective methods of providing emergency escape breathing apparatus for all crewmembers on freight trains carrying hazardous materials that would pose an inhalation hazard in the event of unintentional release and then require railroads to provide these breathing apparatus to their crewmembers along with training.
A synopsis of the accident investigation report, including the findings, probable cause and safety recommendations, can be found on the "Publications" page of the Board's web site, www.ntsb.gov. The entire report will appear there in several weeks.
The National Transportation Safety Board (NTSB) is an independent federal agency charged with determining the probable cause
of transportation accidents, promoting transportation safety, and assisting victims of transportation accidents and their families.