The airborne radioactivity area is a room, enclosure, or area in which airborne radioactive materials, composed wholly or partially of licenced material, exist in concentrations that (1) exceed the derived air concentration limits (DACs), or (2) would result in an individual present in the area without respiratory protection exceeding, during those hours, 0.6 percent of the annual limit on intake (ALI) or 12 DAC-hours.