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
"practical"?
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
20.1101)