The Department of Health, Education and Welfare yesterday released a revised set of federal standards for construction and use of hospitals, relaxing the guidelines in the face of a national furor.

In announcing the revised guidelines, HEW Secretary Joseph A Califano Jr. said they are "tough enough to be effective, reasonable enough to be fair." He indicated that the basic revisions have been made with rural areas in mind and that the changes give local health planning agencies "ample authority and ample flexibility to make exceptions are appropriate."

House health subcommittee Chairman Paul G. Rogers (D-Fla.), one of the authors of the 1974 health planning act, under which the guidelines were first announced last September, said yesterday that the changes "respond to both congressional concerns and those raised by individuals and groups who would be affected by the guidelines." He said the changes "make it clear" that decisions about adequacy of health services "will be made at the local level."

When the HEW guidelines were first issued. Califano estimated they could result in the elimination of 100,000 unnecessary hospital beds across the country. In the uproar that followed, hospitals - especially in rural representatives to complain that the guidelines could put them out of business.

According to Califano, HEW received 55,000 comments - 43,000 from Montana, Iowa and Texas.

Among the changes announced yesterday was a relaxation of guidelines for newborn deliveries and care in smaller hospitals, and elimination of guidelines concerning pediatric care in rural hospitals.

The standards, which are intended to guide state and local planning bodles or "health systems agencies" as they draft plans for additional hospital beds and equipment, still include the basic rule of thumb that an area should have no more than four beds per 1,000 population and that they should be at least 80 per cent occupied.

The revised standards also relaxed guidelines for open heart and other cardiac procedures and purchase of computed tomographic scanners - a sophisticated X-ray device.

Enforcement of the guidelines, which are advisory and not mandatory, is left to state planning bodies under the 1974 law. The federal government, in the absence of state action, has no legal authority to cut off hospital funs to areas or hospitals that do not conform.