What is it? A gamma monitor checks for residual radiation before anything leaves Fort Calhoun Station’s Protected Area (PA). There are person-sized monitors that workers stand in prior to leaving. There are also large gamma monitors that scan vehicles departing the PA.
Are they safe? Yes, and sensitive, too. Radiation is a naturally occurring phenomenon – see this collection of background information from the Nuclear Regulatory Commission. The site’s gamma monitors can detect minute changes in the radiological environment. For example, individuals who have had a recent medical radioisotope test or have been around materials containing naturally occurring radioactivity such as clay tiles or ceramics, can cause the monitors to alarm.
Radioactivity vs. radiation – same difference? No, but they’re related. Radioactive solids are particulates of certain elements such as radon, uranium and thorium that exist in Earth’s natural environment. Radioactivity can be found in everything from smoke detectors to hash browns to nuclear fuel. Gamma radiation is a wave emitted from those elements and, if not properly managed, large doses of it could be harmful. These monitors check for any residual gamma radiation at an incredibly minuscule level.
What if the monitor alarms? OPPD maintains a team of radiation protection technicians that are highly trained in the science of managing radioactive material. As the plant moves through decommissioning, these “RP techs” monitor and mitigate potential sources of radiation. If a gamma monitor was to alarm, the tech would investigate and step through comprehensive procedures to ensure the public and OPPD employees remain safe.
So, nobody glows? Only from the pride of a job well done.