National Transportation Safety Board
Office of Public Affairs
Washington, DC - The National Transportation Safety Board today determined the probable causes of two Washington Metropolitan Area Transit Authority (WMATA) Metrorail accidents that resulted in three employee fatalities, and called on WMATA to tighten rules governing wayside worker safety.
"The safety provisions that are in place are understandably geared to the thousands of the daily Metro commuters," said NTSB Chairman Mark V. Rosenker. "However, we also need to make sure that the same attention to safety is established for employees who service and maintain the track, signals, and railcars for the Metro system."
On Sunday, May 14, 2006, a southbound WMATA Metrorail Red Line subway train struck and killed a Metrorail employee as the train was about to enter the Dupont Circle station in Washington, D. C. The employee was an automatic train control system mechanic who had been working with two other mechanics at the interlocking just north of the Dupont Circle station. All three mechanics had moved between the two main tracks north of the interlocking in order to stay clear of a northbound train that was leaving the station. As the southbound accident train was arriving, the other two mechanics remained in the clear between the two trains as they passed and were not injured. According to signal system data logs, the southbound train was moving about 40 mph as it traveled past the interlocking.
The Safety Board determined that the probable cause of the Dupont Circle accident was the failure of the automatic train control system mechanic to stay clear of the approaching southbound train either because he was not aware of the presence of the train or because he lacked a physical reference by which to identify a safe area outside the train's dynamic envelope.
On Thursday, November 30, 2006, a northbound WMATA Metrorail Yellow Line subway train struck and fatally injured two Metrorail employees who were performing a routine walking inspection of main track near the Eisenhower Avenue Metrorail station in Alexandria, Virginia. The accident occurred as the northbound train was traveling about 35 mph along track normally used for southbound traffic.
The Safety Board determined that the probable cause of the Eisenhower Avenue accident was the failure of the train operator to slow or stop the train until she could be certain that the workers ahead were aware of its approach and had moved to a safe area.
Contributing to both accidents were WMATA Metrorail right-of-way rules and procedures that did not provide adequate safeguards to protect wayside personnel from approaching trains, that did not ensure that train operators were aware of wayside work being performed, and that did not adequately provide for reduced train speeds through work areas. Also contributing to these accidents was the lack of an aggressive program of rule compliance testing and enforcement on the Metrorail system.
In the report released today, the Safety Board noted that in both the Dupont Circle and Eisenhower Avenue accidents, train operators ran their trains as if no workers were present or were likely to be present along their routes. The rules and procedures in effect at the time did not require that trains be operated in manual mode or at reduced speeds through work areas, either of which would have given the train operators a better opportunity to respond if wayside workers failed to move into the clear at the approach of a train.
The Safety Board found that the rules cited in WMATA's Metrorail Safety Rules and Procedures Handbook, did not account for the fact that, depending on the sight distance as shown in both accidents, trains being operated at normal speeds may not be able to stop short of wayside workers who are unaware of the train's approach and have failed to move to a safe area. The rules did permit wayside workers to request that the control center reduce train operating speeds in the areas in which they were working, but as revealed by the Board's investigation, such requests were discouraged by train controllers and seldom made.
The Board determined that technology can provide additional protection for wayside workers, especially in a work environment in which a lapse of attention can quickly result in serious injury or death. There is technology that can provide alerts to both the train operator and the wayside workers, the Board noted. These systems provide train operators with an audible and visual alarm when they are approaching wayside workers who are near the tracks and warnings to wayside workers who are wearing a personal warning device. Therefore the Safety Board believes the WMATA should promptly implement appropriate technology that will automatically alert wayside workers of approaching trains and will automatically alert train operators when approaching areas with workers on or near the tracks.
As a result of these accident investigations, the Safety Board made recommendations to WMATA regarding wayside worker protection, compliance of WMATA safety rules, and technologies for wayside worker protection.
A synopsis of the Board's reports, including the probable cause and recommendations, are available on the NTSB's website, www.ntsb.gov, under "Board Meetings." The Board's full reports will be available on the website in several weeks.
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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.