The National Transportation Safety Board is investigating an incident Feb. 14 in which the engineer of a Maryland commuter train was removed from his locomotive at Union Station here and found to be intoxicated, Board Chairman Jim Burnett said yesterday.

Safety board officials said the engineer, who was about to take a 5:28 p.m. Chessie System commuter run to Brunswick, in Frederick County, Md., scored .22 on a blood-alcohol test ordered by the manager of the Washington Terminal. The legal intoxication limit in Maryland is .13; it is .10 in Washington, D.C., where the terminal is located at the station.

John H. Griffin, manager of passenger operations for the Chessie System, said the engineer of the 200-passenger train has been suspended without pay.

He said the engineer, whom he would not identify, appeared before a discipline hearing convened jointly by officials of the railroad and the Washington Terminal soon after the incident. He said he did not know when the result of the hearing will be known.

Griffin said the engineer is an experienced employe who worked in the locomotive with one fireman.

Safety Board Chairman Burnett said the engineer was about to begin his trip to Brunswick and would have been following another commuter train leaving eight minutes earlier. "If the leading train had been delayed, there could have been a risk" that an incapacitated engineer would not have properly read the signals, Burnett said.

According to Burnett, an Amtrak safety officer reported his suspicions about the engineer's condition to another member of the train's crew. When no action was taken, Burnett said, the safety officer reported his observations to a Chessie System supervisor and the engineer was replaced. Griffin said the incident was handled by Washington Terminal officials who had jurisdiction over the train while it was in the area and who took the engineer for a blood test.

He said he thought the Feb. 14 incident was unusual. "I have been in the railroad for 40 years, and in passenger service for 10 years, and this is the first instance like this in the passenger department that I know of," he said.

Safety board officials said they think the incident illustrates the need for the Federal Railroad Administration to establish regulations on alcohol and drug use by railroad employes. Board spokesman Ira Furman said the board would like to see a rule, similar to one set for airplane pilots, forbidding train operators from drinking for several hours before they take the controls.

Furman said that in a 1978 survey of 234,000 railroad workers conducted by the Federal Railroad Administration, 15 percent said they had reported to work "very drunk" on at least one day during the previous year, and 15 percent of those surveyed said they had been "slightly drunk."