The National Transportation Safety Board opened public dockets Wednesday for investigations of three accidents that occurred in the last 18 months in the Metrorail system.

The accidents include a Nov. 29, 2009 crash at a West Falls Church rail yard, which injured three workers and damaged several rail cars; a Jan. 26, 2010 accident on the Red Line that killed two track workers; and a Feb. 12, 2010 derailment near Farragut North Station.

Three Metro employees were injured when a train headed into this West Falls Church rail yard hit another parked train. (Linda Davidsoon/The Washington Post)

The creation of the dockets marks the release of factual information about the accidents and does not provide any analysis of the events, which will be released later, the NTSB said. The material includes exhibits, transcripts, photographs and other documents. Officials said the NTSB would not conduct any interviews on the information.

The accidents being investigated by the NTSB were part of a series of tragedies in the transit network that began with the fatal Red Line crash in June 2009 that killed nine people. In the ensuing months, four workers died in accidents and several were injured.

The NTSB at one time had four open investigations into Metro, including the Red Line probe .

“No one can recall another time when the NTSB has had four open investigations involving a single transit system,” NTSB spokesman Peter Knudson told The Post last year. “When we see numerous accidents in a relatively short period of time, we want to determine what, if any, common elements there are that may need to be addressed.”

The NTSB concluded in its final report on the Red Line crash that a negligent attitude toward safety permeated Metro and was one of the causes of that accident.

Since the spate of accidents, Metro has hired a new general manager and the authority has several new members on its board of directors. The Tristate Oversight Committee, the safety supervisory agency for Metro which was criticized in the wake of the crash as being ineffectual, gained new power.

Metro chief Richard Sarles recently said during a meeting with the Post’s editorial board that the agency has made vast strides in safety, filling vacancies in the safety department and changing workplace attitudes.

“Safety remains No. 1,” he said.