The Washington Hospital Center is under investigation by the Nuclear Regulatory Commission because of two recent accidents in which an employe and a wrong patient received doses of radiation.

An official of the Philadelphia regional office of the NRC confirmed yesterday that hospital officials had been summoned to an enforcement hearing Friday to discuss a Jan. 9 incident in which a technician accidently was exposed to radiation. Federal regulators said they will take no action in the second accident, involving a radiation dose being given to the wrong patient, as it was a doctor's error and is not covered by NRC rules.

The problems at Washington Hospital Center are shared by many hospitals nationwide, according to federal regulators, as cancer treatments, organ transplants and other procedures using radiation become more numerous. Documents released to The Washington Post under the federal Freedom of Information Act show a wide variety of problems with radiation safety at nearly every area hospital.

In the Jan. 9 incident at Washington Hospital Center, a locking device that halts operation of the machine that administers cobalt-60 radiation treatment malfunctioned, according to John Glenn, chief of the regional NRC office of nuclear materials safety, but the hospital continued to operate the machine. As a result, a technician was exposed when she entered the room prematurely.

"There's an extensive fail-safe mechanism of lights and locks, but apparently they did not work," said hospital spokeswoman Stephanie McNeill. "The technician said she thought she heard the radiation source move to the shielded position. A second technician called to her that the source was still on and hit the off switch."

The technician, whom the hospital said received 4 rems of radiation, is being checked periodically for any ill effects, McNeill said. By comparison, an ordinary X-ray exposes a person to 10 to 50 millirems, or thousandths of a rem. McNeill said the exposure represents an "insignificant dose" of radiation.

The accident caused the hospital to replace the section chief of radiation therapy because he had been told earlier in the day about the malfunction by the radiation safety officer, McNeill said. Neither the section chief nor the safety officer reported the incident to the NRC until the following day, despite federal rules requiring immediate notification.

McNeill blamed the accident on the radiation safety officer's attempt to correct the problem himself so that a backlog of patients didn't develop.

In a second incident at 9 a.m. on Feb. 7, a woman who had just received a kidney transplant received 150 rads (or radiation absorbed doses) intended for another transplant patient. Radiation is used after a transplant to help kill immune responses that might trigger organ rejection. The woman involved in the incident was not scheduled to receive radiation therapy, however.

In a preliminary report on the accident, the NRC said the wrong patient, along with an incorrect request form bearing the wrong patient's name, was sent to the radiation therapy department. The mix-up was discovered at 4 p.m. and the NRC notified immediately, McNeill said.

Dr. Sidney Wolfe, director of the Health Research Group, a public interest organization concerned about the hazards of radiation, said 150 rads is the equivalent of some 6,000 chest X-rays.

The hospital could receive a fine of up to $5,000 for failure to follow federal procedures, Glenn said.