The House ethics committee adopted a tough set of operating standards yesterday, putting congressmen who accepted cash or gifts from the South Korean government on notice that they would be thoroughly investigated by their colleagues, even if they escape criminal prosecution.

In a three-hour executive session that finally launched their active investigation of South Korean influence-buying, members of the often-maligned committee:

Voted on eight policy recommendations by special counsel Philip A. Lacovara, agreeing in each instance to hold House members accountable to a higher standard of conduct than they would have to face in a criminal court.

Authorized issuing what one member said were dozens of subpoenas and requests for information from potential witnesses.

Heard for the first time the names of present and former members who have come under scrutiny by the committee's special team of attorneys and investigators. These names were not disclosed.

The actions yesterday seem certain to widen the reach of the committee's investigation to include several sitting Congressman.

For instance, the committee approved Lacovara's suggestion that members who accepted free trips to South Korea to accept honorary degrees be called to explain their conduct. Several current members reportedly have taken such trips.

Rep. John J. Flynt (D-Ga.), chairman of the committee, said after the closed meeting that there had been near unanimous agreement among the members in accepting Lacovara's strict interpretations for judging members' conduct.

In a key point, the committee agreed that members should be punished for accepting gifts if they neglected to ask the purpose of the gift. Criminal law requires that a person have actual knowledge the gift was meant to influence him before he can be prosecuted.

In his 83-page "Manual of Offenses and Procedures' Lacovara referred to this stricter standard as a member's "affirmative duty of reasonable inquiry."

The Washington Post reported last Sunday that several former and one current member of Congress had written to South Korean President Park Chung Hee in early 1973 praising the work of Washington businessman Tongsun Park, who now is a central figure in a Justice Department investigation.

Several of those members have acknowledged receiving gifts or cash payments from Park as well as doing favors such as writing laudatory letters at his request.

The committee decision yesterday requiring "affirmative inquiry" thus seems to mean that those member should have been more skeptical of Tongsun Park's generosity and his connections with the South Korean government.

Along the same time, Flynt said yesterday, the committee adopted a requirement for "clear and convincing" evidence for disciplinary proceedings, rather than the criminal courts' more demanding "beyond a reasonable doubt" standard.

The current Justice Department investigation of South Korean gifts and payments to past and present members of Congress has been hampered because of missing witnesses, the difficulty of proving cash payments and knowledge of intent by the recipient.

Flynt said the committee also agree to pursue only gifts of more than $100 in value, unless they were part of a pattern of misconduct by members. "That's to keep our investigators from having to go out on rabbit hunts when they should be after big game," he said.

Several members of the committee said after the executive session that they were pleased the investigation finally is gathering speed.

Rep. Bruce Caputo (R-N.Y.), a new member, complained during the open session that the public might think the committee's slow pace so far indicated a reluctance by Congress to investigate itself.

The other members disputed his suggestion to proceed immediately with a test case against a member who has acknowledged receiving gifts.