The following is a synopsis of information received from the
New Mexico Radiation Control Bureau (NMRCB):
On October 22, 2019, a worker was manually drilling a container with 1080 millicuries of iridium-192 in ceramic tracer beads. The worker was not wearing eye or face shields and a puff of dust from the drilling struck the worker's face and eyes. Immediately after, the worker repeatedly washed their face and eyes. On the next day, a survey of the worker's face/eye area showed 200 mR/hr. Subsequent surveys over the next 103 days showed steadily decreasing amounts, down to 10 mR/hr at 103 days.
On June 23, 2020, the NMRCB reached out to the NRC seeking assistance in determining the individual's dose. Staff from the Office of Nuclear Material Safety and Safeguards (NMSS) and Region IV Division of Nuclear Materials Safety (DNMS) held a call with NMRCB, providing options on how to proceed, including encouraging the individual submit to a full body count. A whole body radiobioassay was performed on July 17, 2020, 272 days after the exposure. The result on the first run was 4.12 nCi and 4.34 nCi on the second run. NMRCB used RCD Radiation Protection Associates, an NRC contractor, to develop a dose assessment of the exposure event.
In a reported dated November 18, 2021, (
ML21354A314) RCD Radiation Protection Associates presented results indicating a committed effective dose equivalent (
CEDE) to the worker of 1.48 millirem, a shallow dose equivalent (
SDE) estimated to be 663
rem, a lens dose equivalent (
LDE) estimated to be 11.5
rem, and an effective dose equivalent (EDE) of 3.6 millirem.