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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)