Federal workers in the Washington metropolitan area were hit harder last year by layoffs, demotions and forced retirement than those in any other part of the country, according to a congressional study released yesterday.

Forty-five percent, or 1,387, of the reductions-in-force (RIFs) nationwide in fiscal 1984 occurred in the Washington area, although only 12.5 percent, or 340,000, of the nation's federal workers lived here, according to the Federal Government Service Task Force, a congressional group that prepared the report.

The RIFs included four groups of workers: those "separated" from their jobs or laid off; those "downgraded" or demoted; those given lateral transfers to jobs of equal pay, and those forced into retirement.

There are more than 2.7 million federal workers nationwide, including defense and postal workers.

The second hardest hit area in fiscal 1984 was Region 9 (California, Hawaii, Arizona, Nevada), which accounted for 13.9 percent of all actions or less than one-third of the RIFs that occurred in Washington. Region 2 (New Jersey and New York) had less than 1 percent of the total RIFs.

The Washington area was also the only region that had an increase in the number of RIFs from fiscal 1983 to 1984. In fact, RIF activity nationwide fell by 22 percent in fiscal 1984.

But in the nation's capital, the number of RIFs rose from 1,049 in fiscal 1983. That year the Washington area accounted for about one-third of the total, according to Robert E. Honig, staff director of the task force.

The task force study said that the regional effects of the RIFs suggest that the reductions were aimed more at policy-level jobs in social service areas.

These activities tend to cluster at headquarter sites, resulting in a heavy impact on Washington.

Honig said that the data also showed that women and minorities were hit particularly hard. He said that this area has a heavy concentration of minority-group members who work for the federal government.

The study found that during President Reagan's first term, a total of 33,845 federal workers were affected by RIFs, and of those 14,490 employees lost their jobs.

In 1981, the Reagan administration announced that it planned to reduce civilian employment in federal agencies by 75,000.

It said most of the reduction would be achieved through attrition and a hiring freeze.

A statement released by Rep. Michael D. Barnes (D-Md.), chairman of the task force, said that the study "refutes earlier claims by the Office of Personnel Management that RIFs played an insignificant role in work force reduction."

A spokesman for OPM declined to comment, saying no one in the agency had seen the report.

The task force, which is composed of 42 Democratic members of Congress and two Republicans, also found that minorities, which accounted for only 24.9 percent of the federal work force, suffered 49 percent of all RIF actions in fiscal 1984.

The Health and Human Services, Labor and Interior departments reported the most RIFs, accounting for nearly half of the total in fiscal 1984.

During the first term of the Reagan administation, HHS and Interior also led with 6,586 and 3,816 RIFs respectively.