The Environmental Protection Agency, under court order, issued a final rule yesterday restricting the use of electrical equipment containing polychlorinated biphenyls, or PCBs.

The regulation got mixed reviews from both industry representatives and environmentalists.

PCBs, found in electrical equipment used by utilities, have been shown to produce liver tumors when fed to mice, and other studies have indicated an increased incidence of cancer among those exposed to them.

In 1976, Congress directed the EPA to ban their manufacture and use.

Two years ago, the agency proposed a rule restricting PCB equipment, but it was thrown out by the courts as too weak. A new proposal was issued in April.

Among provisions of the final rule:

PCBs in transformers or electromagnets that "pose an exposure risk" to food or animal feed are prohibited after Oct. 1, 1985, and until then weekly inspections are required. Other transformers or electromagnets can be used until they wear out and must be inspected regularly.

PCB capacitors located near food or feed or outdoors in an area where the public could be exposed, such as on telephone poles, must be phased out by Oct. 1, 1988. Those in restricted areas can be used for their remaining "useful life." Capacitors will not have to be inspected.

Corey Trench, an environmental scientist with the Edison Electric Institute, the utilities' trade group, said the new rule will mean phasing out 1.5 million capacitors over the next six years. Trench also criticized the EPA for expanding the "food and feed" rule to include facilities like restaurants and grocery stores.

Dr. Ellen Silbergeld, a scientist with the Environmental Defense Fund, said her group was "disappointed" that the EPA had allowed much of the equipment to be used for its "useful life."

Bob Fensterheim, of the Chemical Manufacturers Association, said his group was pleased that the EPA made a distinction between capacitors where the risk of public exposure is great and those where it is not.A CMA spokesman noted that its major concern is over PCBs produced inadvertently in manufacturing, which is the subject of a separate rule-making proceeding.

The rules will take effect 30 days after they are published in the Federal Register in about 10 days.