RICHLAND -- Lab results received so far show that Hanford workers exposed to tritium last month had very low levels of the radioactive isotope.
Workers were removing an exit sign at the 326 Building, which dates to 1953, when tritium capsules broke. Tritium commonly was used in illuminated signs of that era. The sign had been covered with a newer sign and workers didn't realize the capsules were there, according to Washington Closure Hanford.
"We are looking into ways to improve our processes," said Washington Closure spokesman Mark McKenna.
Bioassays were collected from everyone in the eight-person crew as a precaution. Ten other workers in the area also requested bioassays.
In the seven bioassays of crew members completed, less than 1 millirem of radiation exposure was detected.