Congress has approved and sent to the White House legislation to ban most uses by private employers of lie detectors, described by one senator as "inaccurate instruments of intimidation."

The Senate voted 68-24 on Thursday to approve a compromise version of a House-passed bill that would prohibit most polygraph tests. Labor Secretary Ann Dore McLaughlin has said she will ask President Reagan to sign the bill.The final version of the legislation, approved by House-Senate negotiators last month, would prohibit most private sector employers from requiring their workers or job applicants to take lie detector tests. Exceptions would be made for drug companies and those providing security services.

The bill would prohibit an employee from being discharged, dismissed, disciplined, discriminated against, or denied employment or promotion solely on the basis of the test - or solely because of refusal to take the test. To take action against the worker, an employer would have to have additional supporting evidence.

The Congressional Office of Technology Assessment estimated that 2 million polygraph tests were administered in 1987, with 90 percent given by private employers. Most of those were job applicants, although they also were given to workers under investigation.

The accuracy of test results has been questioned, and so has the competency of some examiners.

Sen. Edward M. Kennedy, D-Mass., chairman of the Senate Labor Committee, called the legislation "long overdue."

"For too long, we have known the widespread and growing use of these so-called lie-detectors was subject to misuse and abuse," he said before the Senate voted.

Judy Goldberg of the American Civil Liberties Union said the law will affect 28 states that have no regulation of polygraph examinations or regulate only the examiners.

Utah regulates polygraph examiners only.