What area classification is defined by a potential concentration greater than 1 DAC?

The correct classification for an area where there is a potential concentration of airborne radioactivity greater than 1 Derived Airborne Concentration (DAC) is indeed the Airborne Radioactive Area. This classification is specifically applied to locations where airborne radioactive materials are present at levels that could lead to significant inhalation or ingestion of radioactive substances by individuals exposed in that area.

In defining a DAC, it refers to the concentration of radioactive material in the air that results in a dose of 1 Occupational Dose Limit within a working year, assuming normal breathing rates and exposure times. Therefore, when airborne radioactivity concentrations exceed this threshold, protective measures and monitoring are critical to ensure the safety of personnel.

Other classifications, such as Radioactive Material Area, High Radiation Area, and Very High Radiation Area, pertain to different forms of radiation hazards associated with material contamination or gamma radiation exposure directly from sources, rather than airborne concentrations. Each of these classifications serves to identify and mitigate various risks related to radiation exposure, but the specific concern of airborne concentrations is distinctly addressed by the Airborne Radioactive Area classification.