United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

U.S. Nuclear Regulatory Commission

Question 412: This question refers to the answer to

Question 26 (b) under §20.1003. What is the basis for

using a dose threshold to decide whether a person is

categorized as a member of the public or as occupationally

exposed? The definitions do not specify a dose threshold.

Answer: Question 26 (b) asked whether occupational or

public dose limits apply to individuals, described in three

different scenarios, who are exposed within controlled

areas (outside any restricted areas) at a nuclear power

plant. These scenarios described (1) a fossil plant

worker, (2) a pregnant taxi driver, and (3) construction

workers building a second nuclear power plant and

secretaries in the administrative building. The answer to

Question 26 (a) states that the public dose limits apply to

the individuals in all three scenarios, but the answer also

states that if turbine shine from the nuclear plant is such

that fossil plant workers, construction workers, or

secretaries (but not the pregnant taxi driver) ". . . are

likely to exceed the dose limits for members of the public,

the licensee should consider the individual doses to be

occupational doses and meet the requirements for

individuals who receive occupational doses." The basis for

this answer is the NRC staff's understanding of the intent

of the definition of "occupational dose", specifically,

that portion which states that "occupational dose means the

dose received by an individual . . . in the course of

employment in which the individual's assigned duties

involve exposure to radiation . . . ." This understanding

of the definition is also expressed in more general terms

in the answer to Question 26 (a). (Reference: 10 CFR


Page Last Reviewed/Updated Thursday, March 29, 2012