A staff report of the congressional Joint Committee on Atomic Energy obtained yesterday accuses the Nuclear Regulatory Commission of "serious management deficiencies" in handling nuclear safety issues.

The assessment was made after an investigation of charges of NRC scientists that their warnings about safety problems at nuclear power plants were being ignored or suppressed by their superiors.

Because of the "insensitivity" of the NRC to the complaints of its staff, the reports says, "government forces outside of the commission will have to be used to assure that changes are made at the earliest possible date."

The report says there should be a shakepup in NRC management but does not criticize individuals by name.

The report says that when the NRC was created in January, 1975, out of the old Atomic Energy Commission, the regulatory program already "suffered from a lack of effective management." The NRC thus "inherited" a "helter-skelter arrangement" and made no effort "to strengthen or even evaluate or question management of the regulatory program."

The joint committee has pointed out to the NRC, the report says, that the rapid growth of its responsibilities and staff in recent years posed "a special challenge to the management," but the NRC "took no effective action on the subject" despite "all of the favorable assurances given by NRC officials in testimony before this committee . . ."

NRC scientists with the responsibility of reviewing designs of nuclear reactors and other power plant components submitted by manufacturers and utility companies must be able to raise technical questions "without any fear of reprisals," the report says.

About a dozen scientists complained in confidential interviews last October that their warings about safety were being ignored by the NRC hierarchy and that they were afraid to be publicly identified with the issues lest they be blacklisted by the NRC and the nuclear industry.

Several subsequently "went public" with appearances before the NRC's Advisory Committee on Reactor Safeguards and a hearing in December before the Senate Government Operations Committee.

Twenty-seven separate safety issues were identified. Other NRC scientists assigned to review the official position on each issue categorized them into five major groupings of technical functions at a nuclear plant:

The overall electrical system: instruments powered by electricity that operate the plant; backup safety systems designed to shut down the reactor in case of emergency and perform other safety support operations; accident prevention systems, and the efficiency of administrative procedures at power plants.

Because of the potential for disaster inherent in a nuclear plant through possible release of radioactivity in lethal quantities, every nut, bolt pipe and piece of machinery must be manufactured and put together according to detailed NRC specifications.

NRC scientists must review designs each step of the way in construction for opposite error or inadequacy. When mistakes are found it is costly to the industry through delay and the need to redesign and even rebuild.

Some of the 27 issues still are under review by the NRC, but the agency maintains none are of a nature that requires plant shutdown.

NRC Chairman Marcus A. Rowden and Ben C. Rusche, director of the Office of Nuclear Reactor Regulation, both issued statements maintaining they had an open-door policy and any staff member was welcome to bring problems to their attention.

Rusche also solicited memos from dissenters and set up a specific system for bringing forth "dissentening technical viewpoints."

However, in the judgement of the Joint Committee staff, these steps were not enough to "restore the trust and confidence of its professional employees in management."

The "major problem," the Joint Committee staff said, "is the lack of effective management within NRC. Action is needed which will assure that competent managers fill important positions . . ."

The report represents the findings of the Join Committee staff headed by executive director George F. Murphy Jr. Murphy said "three or four" staff members participated in their viewing NRC scientists, reviewing documents and preparing the report.