United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

U.S. Nuclear Regulatory Commission

Question 4: How is the dose from radon considered? What

about technologically enhanced radon at a licensed

facility? [Note: Technologically enhanced natural

radiation sources have been defined as "truly natural

sources of radiation . . . which would not occur without

(or would be increased by) some technological activity not

expressly designed to produce radiation." Reference: T.F.

Gesell and H.M. Prichard, Health Physics 28, 361-366, April


Answer: How the dose from radon is treated depends upon

the source of the radon. If the source is NRC-licensed

material such as mill tailings or ores, then the dose from

radon and its particulate daughters should be included in

estimates of doses to workers or to members of the general

public (except for 40 CFR Part 190 evaluations which

exclude radon). If the source of the radon is from radium

that is not licensed or controlled by any agency, then the

dose from radon and its daughters is considered background

radiation and may be excluded from occupational or public

dose estimates, whether there is any technological

enhancement of the concentrations or not. Many states are

working toward licensing certain materials containing

radium and these sources will need to be known to licensees

even if they are not the persons licensed by the States.

(See definitions of "background radiation," "source

material," and "byproduct material" in 10 CFR 20.1003).

(References: 10 CFR 20.1001, 10 CFR 20.1002, 10 CFR


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