A blind New Carrollton woman was critically injured yesterday morning when she was struck by a Metro subway train as it entered the Foggy Bottom station.

The woman, 27-year-old Patricia A. DeBoard, was on her way to work at George Washington University hospital, where she is employed in the medical records section. Officials said she has ridden a train from New Carrollton to Foggy Bottom, her normal pattern. She was struck on the opposite track, however -- the one for trains coming from Virginia to D.C. The platform is in the middle at that station.

The 6:55 a.m. incident slowed rushhour subway service on the Orange and Blue lines for almost an hour.

The Metro train operator, J. L. Harrison, told his supervisors that he saw a woman on the tracks just as his train was entering the station. He pushed his emergency stop button, but the train was probably traveling at about 30 mph when it hit DeBoard.

About 2 1/2 cars of the six-car train had entered the Foggy Bottom station before the train was stopped. DeBoard was under the second car.

She was taken to George Washington University hospital suffering from "multiple traumas," according to a hospital spokesman. After surgery, hospital officials said, she was placed in the intensive care unit in "very critical" condition.

DeBoard's guide dog was not injured and was turned over to other family members by D.C. police.

Jim McDonald of Woodbridge said he was a passenger in the first car of the train. He said another passenger seated immediately behind the operator's cab "made a sound, not a scream, then pushed his feet on the floor like he was trying to put on the brakes . . ." just before the train struck the woman

Passengers were put off the train at Foggy Bottom and the station was closed. Other trains single-tracked around the scene and did not stop at Foggy Bottom until about 8 a.m., when service returned to normal.

Officials were uncertain yesterday why the woman was on the tracks. "We're carrying it as an accident," said D.C. police spokesman Gary Hankins. "There is nothing to indicate that she jumped."

There is a granite strip immediately parallel to the tracks on Metro's station platforms. One of its purposes, Metro officials have said over the years, is to alert blind people to the fact that they are approaching the edge of the platform. The rest of the platform floor is made of tile.