U.S. Nuclear Regulatory Commission

Question 436: Licensees are required to "reduce the dose

that an individual may be allowed to receive in the current

year by the amount of occupational dose received while

employed by any other person." How should this provision

be applied to dose categories required to be monitored by

the current licensee, for which the individual's dose

report (e.g., NRC Form 5) from previous employment during

the current year at another licensee's facility indicates

"NR" (not required), "ND" (not detectable), or is left

blank? May the dose in categories denoted on the dose

record as "NR", "ND", or left blank be assumed to be zero,

and therefore no reduction be made to the dose that the

individual may be allowed to receive in the current year?

Answer: Yes, for cases in which "NR" or "ND" have been

recorded. However, if there is no recorded dose for a

dose category and no reason for this omission has been

provided (i.e., "NR" or "ND" have not been entered), the

licensee should determine if the dose value has been

omitted erroneously before assuming it to be zero (e.g., by

checking with the licensee that provided the Form 5 with a

dose category left blank). If the licensee cannot

determine why there is no recorded dose for a dose

category, the licensee has been unable to obtain a complete

record of the individual's dose history for that dose

category and the individual's exposure must be limited in

accordance with 10 CFR 20.2104 (e) (1). (Reference: 10

CFR 20.1201, 10 CFR 20.2104, Regulatory Guide 8.7, Rev. 1).