United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Question 176: 10 CFR 20.1201 (a) (2) (ii) states a limit

of "A shallow-dose equivalent of 50 rem (0.50 Sv) to the

skin or to any extremity." (a) Can a person receive 50

rem shallow dose equivalent to the skin of the lower arm

(extremity) and 50 rem shallow dose equivalent to the upper

arm non-extremity), without having an overexposure? (b)

Can a person receive 50 rem shallow dose equivalent to the

left upper arm, then the same dose to the right upper arm,

without having an overexposure? (c) Can a person receive

50 rem shallow dose equivalent to each extremity during one

year?



Answer: (a) Yes, as long as the total shallow dose

equivalent does not exceed 50 rem in either position. The

skin of the extremity is not considered in the shallow-dose

equivalent limit to the skin of the whole body. The annual

limits are a shallow-dose equivalent of 50 rem (0.50 Sv) to

the skin or to any extremity.



(b) Again, as long as it can be shown that the total

shallow dose equivalent does not exceed 50 rem at any one

location on the skin of the whole body, there is no

violation. If the two different areas of the skin of the

whole body each receives 50 rem total shallow dose

equivalent during the year, then the limit has not been

exceeded.



(c) Yes. The regulation states ". . . or to any

extremity;" therefore, a worker may receive a shallow-dose

equivalent of 50 rem to each of the four extremities.

(Reference: 10 CFR 20.1201, 10 CFR 20.1003, Regulatory

Guide 8.34)

Page Last Reviewed/Updated Thursday, March 29, 2012