The adequacy of Metro's preparations for emergencies on the subway was called into question again yesterday by unrelated incidents that fouled up both Wednesday evening's and yesterday morning's rush hours.

It took 69 minutes for Metro personnel to finish evacuating more than 1,000 passengers after a train broke down on the Red Line on Wednesday. Then yesterday morning, a small fire on the Blue/Orange line, while not serious, brought a Keystone Kops quality to the coordination efforts of Metro and the D.C. Fire Department and delayed many commuters for about 30 minutes.

One of the major concerns of safety experts, such as James B. King, chairman of the National Transportation Safety Board, has been the amount of time it would take to evacuate a fully loaded train in an emergency.

King told transit operators at their annual meeting in San Diego last week that the safety board "is concerned about the potential for a catastrophic event" in subways. He encouraged the operators to develop binding standards of safety and emergency coordination if they want to avoid federal regulation.

"Once you're under the gun," he said, "you will have lost your credibility."

A small trash fire in the long Metro tunnel under the Potomac River last April was extinguished after some confusion when communications broke down between Metro and both the Arlington and District fire departments and after Metro had run a train carrying passengers into the smoky tunnel so a supervisor could attempt to find the source of the fire.

Yesterday morning's fire occurred on the New Carrollton-bound track about 50 feet east of the Farragut West station. Flames described to the D.C. Fire Department as being about three feet high were spotted at 8:23 by a train operator.

The operator asked the passengers to leave the train. Then, with third-rail electrical power removed, he put out the blaze with a fire extinguisher. . .

Just as the operator returned to his empty train and prepared to make a test run, the D.C. Fire Department arrived. It had been called after the operator reported the fire. Firemen immediately hit the emergency switch that cuts off all power on both tracks, then checked the area of the fire to confirm it had been extinguished. The second delay totaled 11 minutes. By the time it was all added up, hundreds of passengers in both directions were delayed.

Metro does not like to have the fire department immediately turn off third-rail power because of the possibility that trains might need to be moved away from an emergency. Deputy D.C. Fire Chief Hubert Clarke agreed with that concern yesterday.

"We definitely need to start restraining our people," Clarke said. "In a hypothetical situation, [removing electrical power] may be doing exactly the opposite of what you want. . . ." Clarke said that many firemen and recently promoted supervisors have little experience in the Metro tunnels.

Clarke said the fire apparently occurred when a small spill of a petroleum substance, possibly hydraulic fluid or diesel fuel from a work train, was ignited.

The evacuation scene Wednesday evening was all Metro's show. A train bound for Silver Spring stalled for reasons still undetermined on an elevated, curved section of track just south of the Rhode Island Avenue station.

Attempts were made to couple the train to another train and pull it or push it out.But coupling requires a straight section of track, and the attempts were unsuccessful. Then, an empty train was brought up to the front of the stalled train. At least 1,000 passengers had to walk single file from one train to the other, a slow process.

Both Chief Clarke and Metro General Manager Richard S. Page said they were bothered by the length of time it took to evacuate the train. "It's a major concern to us," Clarke said, "especially if it happened in a tunnel and there were a fire situation."

Page said "there are several delays in there that concern me." After the passengers were removed, the train was permitted to coast from the elevated structure into Metro's main repair yard, conveniently located downhill from the elevated section of track. Then it took another 24 minutes before train equipment experts arrived on the scene to get the train moving.

"Given the way these trains are made," Page said, "and given [the fact] that it was on an elevated structure, moving passengers from a loaded train is going to take time. . . . We've got to look at this again and see if anybody was slow to respond and in general see if there are alternatives that can be faster."

Page said an internal investigation is under way at Metro into yesterday morning's fire, and that he had no comment on it.

Page also said that he could not explain why Metro has yet to install in its cars printed instructions to passengers on what to do in an evacuation situation. Wording of the instructions had been coordinated with the fire department, he said. "I had expected them [the instructions] to be in the trains long before now."