The Department of Health, Education and Welfare has asked for permission to allow thousands of senior employees to retire early.

HEW is the third largest federal employer in the Washington metro area, which has 347,000 civil servants. Locally, HEW has 36,000 employees, with another 22,500 at Social Security headquarters in nearby Baltimore.

The giant department's request for early-out retirement authority is pending with the Civil Service Commission, which can approve only if an agency is facing major reorganization and/or job cutbacks.

Nationwide, HEW has about 140,000 permanent full-time workers. Officials estimate that about 8,500 would be eligible to retire if CSC gives the word. That approval is not certain, insiders say.

Under the early-out retirement authority HEW is seeking for many of its major units, anybody in one of those offices or areas could retire if they had 25 years of service. All would be eligible for an immediate annuity but, in the case of workers retiring younger than age 55, their pension would be reduced 2 per cent a year for each year they were under 55.

Normally, the earliest a federal worker can retire on immediate pension is age 55 after 30 years of service. Employees can also retire at 60 with 20 years or at 62 if they have a minimum of five years service.Pensions are based on a combination of service time and salary.

The HEW request, if approved, would cover most headquaters staffers here (if they meet age and service requirements) and workers at the big Food and Drug Administration operation in Rockville. The request also includes Social Security regional and headquarters offices, but would not apply to employees in district and branch offices, to the Bureau of Hearing offices, the Indian Health Service or to health units in other federal agencies.

Officials expect it will be several weeks before HEW finds out whether it will have the early out authority.

Meantime, CSC has approved early retirement authority for the Defense Logistics Agency, the Office of the Secretary of Air Force for National Guard Affairs and for the National Aernautices and Space Administration Goddard Space Flight Center in Greenbelt.

The early out for the Air Force command would run through March 6 while the Defense Logistics Agency early out would expire Feb. 4.

Early out has also been approved for various Defense Property Disposal and Holding Offices, employing thousands of workers. Specific authority has already been granted to those offices in Brandywine and Indian Head and at Pennsylvania bases in Chambersburg, Tobyhanna and Mechanicsburg.