Georgetown University Hospital has won full two-year approval by national accrediting officials after 14 months of what amounted to a one-year probationary status.

The decision was made last week in Chicago by the Joint Commission on Accreditation of Hospitals. It follows five years of effort and the spending of $1.5 million by the hospital to meet tightened fire and safety codes that have given hundreds of American hospitals similar problems. The hospital has installed fire-resistant and smoke-proof partitions and doors and smoke detectors.

"We've done a lot to improve ourselves, but it's been done at a cost," said Dr. John F. Stapleton, the hospital's medical director. The hospital's average daily cost for a patient is $290, said administrator Charles O'Brien Jr. Four percent of that or $11.60 pays for past, present and future building or remodeling.

Both the federal Department of Health, Education and Welfare and the Joint Commission on Accreditation have tightened their safety and medical standards in the past four years. As a result, 40 percent of all hospitals surveyed last year got only one-year instead of their usual two-year approval.

Joint commission officers, however, deny that one-year accreditation is any less "full" approval than two-year approval.

In August 1976 JCAH inspectors applied their latest "life safety" codes, and in December, the hospital was told that it was being reaccredited for only a year. Last October, the inspectors made the survey that has restored twoyear approval.

Several other area hospitals have received only one-year accredition after recent surveys.