Question 40: Assume a licensee has defined its compliance
year as January 1, 1993 to December 31, 1993. What is the
mechanism to change its definition of year? For example,
the licensee wants to monitor from January 31, 1994 to
January 30, 1995, how should it account for the lost days
January 1 - 30, 1994? Is it acceptable to prorate the
doses?
Answer: No. The question refers to the definition of
"year" in 10 CFR 20.1003. The licensee is not allowed to
make the one-step change as postulated in the example in
the question because that change involves omitting certain
days. Omitting days, even with dose proration, is not
allowed. However, the license could accomplish the desired
change in two steps, one step in each of two consecutive
years, that would give a "year" beginning 1/31 of one
calendar year and ending 1/30 of the following year. The
first step, using the example, would be a change, at the
beginning of 1993, to a "year" of 1/1/93 to 1/30/94 (13
months). The second step would be a change, at the
beginning of 1994, to a "year" of 1/31/94 to 1/30/95. This
two-step change meets the requirement of "years" that begin
in January with no day omitted or duplicated in consecutive
years. (Reference: 10 CFR 20.1003)