United States Nuclear Regulatory Commission - Protecting People and the Environment

U.S. Nuclear Regulatory Commission

Question 133: 10 CFR 20.1101 (b) requires licensees to

use, to the extent "practicable," procedures and

engineering controls based upon sound radiation protection

principles to achieve doses that are ALARA. The ALARA

concept emphasizes dose-reduction techniques that are

reasonable considering costs.

However, "practicable" may imply something that has been

proposed and seems feasible but has not been actually

tested in use. "Practical" is more consistent with the

ALARA concept because "practical" implies "sensible",

"involving good judgement" and "proven success in meeting

the demands made by actual living or use." In making

decisions about ALARA procedures and engineering controls,

will licensees be permitted to interpret "practicable" as


Answer: In the context of this regulation, the word

"practicable does not have the connotations attributed to

it in the question. 10 CFR 20.1003 states that "ALARA . .

. means making every reasonable effort to maintain

exposures to radiation as far below the dose limits in this

part as is practical . . . " emphasis added). The

discussion of 10 CFR 20.1101 (b) in the preamble to revised

Part 20 (56 FR 23367) includes the following statement:

"Compliance with this requirement [10 CFR 20.1101 (b)] will

be judged on whether the licensee has incorporated measures

to track and, if necessary, to reduce exposures and not

whether exposures and doses represent an absolute minimum

or whether the licensee has used all possible methods to

reduce exposures." Thus the use of the word "practicable"

in 10 CFR 20.1101 (b) does not imply procedures and

engineering controls that are unproven. (Reference: 10 CFR


Page Last Reviewed/Updated Thursday, March 29, 2012