Alert

Due to a lapse in appropriations, the NRC has ceased normal operations. However, excepted and exempted activities necessary to maintain critical health and safety functions—as well as essential progress on designated critical activities, including those specified in Executive Order 14300—will continue, consistent with the OMB-Approved NRC Lapse Plan.

Health Physics Questions and Answers - Question 27

Question 27: Do licensees have to post controlled areas (outside the restricted area) as airborne radioactivity areas if derived air concentrations (DAC) are exceeded?

Answer: Yes, if the airborne radioactivity is indoors. If the airborne radioactivity is outdoors, the answer depends on the particular situation. In certain situations the licensee may need to identify and delineate an outdoor airborne radioactivity area. For example posting would be required in a small area, accessible to workers, in the immediate vicinity of a vent on the outside of a building, exhausting air containing concentrations of radioactive materials in excess of the DACs specified in Appendix B to 10 CFR Part 20.

(References: 10 CFR 20.1003, 10 CFR 20.1902)

Page Last Reviewed/Updated Friday, November 24, 2017