U.S. Nuclear Regulatory Commission

Question 117: Does the requirement of 10 CFR 20.2101 (a)

to use the unit curie (for activity) mean that it will not

be permissible to record the results of contamination

surveys in units of disintegrations per minute (dpm) or

mrad smearable?



Answer: No. The 10 CFR 20.2101 (a) requirement as it

applies to units of activity (curies) is intended to apply

to records of quantities of material directly related to

the explicit requirements of Part 20 (e.g., storage and

control, posting and labeling, waste disposal,

concentrations in air, and individual intakes of

radioactive material). It is not intended to apply to

surveys for contamination. Note: There are requirements

in 10 CFR 35.70 (h) which apply to medical licensees to

record the results of surveys for removable contamination

as disintegrations per minute per 100 square centimeters.

(Reference: 10 CFR 20.2101)