Preliminary calculations indicate that the radiation dose from Monday's release at the Byron Generating Station was less than 0.001 (one one-thousandth) percent of the commission's annual dose limit of 100 millirems. That amount is thought to be safe to workers and the public, agency spokeswoman Viktoria Mitlyng said.
"That is a very, very, very small amount," Mitlyng said, much less than the dose from a dental X-ray (0.5 millirem) or a smoke detector (0.008 millirem). Exposure to radiation increases a person's lifetime risk of cancer, so minimizing exposure is a good idea.
Monday's outage started when an electrical insulator, a piece of protective equipment that helps regulate the flow of electricity in the plant's switchyard, failed and fell off the metal structure to which it was attached. That interrupted power and caused the reactor to automatically shut down as a precaution.