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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 74

Question 74: Dose rates are used to establish posting requirements for radiation areas, high radiation areas, and very high radiation areas. 10 CFR 20.1601 (a) (1), "Control of Access to High Radiation Areas," refers to a "deep-dose equivalent" in describing when a control device should be provided to reduce radiation doses below 0.1 rem in one hour, thus implying that the "dose equivalent" in the definition of a "high radiation area" is the "deep dose equivalent" [at a tissue depth of 1 cm (1000 mg/square cm)]. Are the "dose equivalent" in the definitions of "radiation area" and "high radiation area" and the "dose" in the definition of "very high radiation area" all considered to be at a tissue depth of 1 cm (1000 mg/square cm)?

Answer: Yes. In addition see Question 57.

(References: 10 CFR 20.1003, 10 CFR 20.1601)

Page Last Reviewed/Updated Wednesday, December 13, 2017