A report dated March 30 is highly critical of fire safety at the research hospital of the National Institutes of Health in Bethesda, where a fire a week ago forced evacuation of more than 300 patients.

The consultants' report said "inconsistency and inadequacy" of the hospital's fire safety system caused "a very real concern about the safety of the building's users."

The report by Maurice Perreault and Associates and Mariani Associates Inc. was studied at a meeting of NIH officials one week before last Saturday's fire, which was called the "worst on record" at NIH.

Two firefighters were injured, and many of the patients evacuated were in the beds or wheelchairs. The fire was on the ninth floor of the 13-story brick hospital that offers new and experimental treatments.

Because the research hospital is federal property it is not subject to local fire codes. Several local fire officials, told of the report's findings yesterday, said that if NIH were covered by such codes, the hospital would be closed.

Jack Leach, an NIH safety officer, said the safety problems are not new. He said officials are reviewing the report's recommendations for upgrading fire safety at the 25-year-old Clinical Center, formal name for the hospital, as part of a major renovation program that could be completed next year.

Leach blames much of the problem on overcrowding. A new building next to the center is scheduled for completion in 1982, he said, and it is hoped that it will provide the extra needed space.

A major conclusion of the report was that flammable and radioactive materials obstructing hospital corridors created "an immediate and continuing danger to staff patients and visitors." It said these materials "are stored in the corridors, boxes are stored on the tops of the cabinets and routine work is done in the corridors." The width of some corridors is "inadequate for even a single-line passage," the report said.

The report also pointed to unlabeled fire doors, insufficient sprinklers and a lack of smoke and heat detectors.

Leach said, "we want to be the model for safety in the biomedical research community. If we made mistakes, they're going to be corrected."

John Morehart, fire safety engineer for the Department of Health, Education and Welfare, NIH's parent agency, said he has been told that "the report has inaccuracies." He said the cluttered corridors are not "as serious a fire hazard as it's being made into. The corridors where the fire occured were not obstructed."

But he said the corridors have been ordered cleared by May 10.

He also said, "if there had been one smoke detector where the fire started, they could have gotten to it a few minutes early, put it out with a fire extinguisher, and the whole thing could have been over in five minutes."

Much of the concern for safety at NIH focuses on the use of potentially dangerous materials such as infectious organisms, cancer-causing substances and toxic or flammable chemicals used in medical research, according to Dr. W. Emmett Barkley, director of the Office of Research of the National Cancer Institute, one of nine institutes with research projects at the clinical center.

"Much of our expertise and attention is directed to hypothetical hazards," he said. "We need to give more attention to actual hazards, everyday hazards, such as fire."

Safety officials who did not want to be identified made two other assertions:

"The government makes rules for safety, but they don't want to abide by them."

Even if present NIH safety polices have enforced, corridors could still have as much as three feet of obstruction, narrowing their effective width to only five feet, which would still violate standard fire codes.