Question 390: During 1993, there may be radiation workers
transiting between licensees that have, and have not,
implemented the revised Part 20. (a) In the case of a
worker whose dose was monitored earlier in the year at a
licensee that has implemented the revised Part 20 and is
now in processing at a licensee that has not implemented
the revised Part 20: (1) Should "whole body dose" be taken
as the "total effective dose equivalent" (TEDE) or as the
"deep dose equivalent" (DDE) recorded by the previous
licensee? (2) If the individual has received dose in
excess of an "old" Part 20 limit for the current quarter,
but less than the respective revised Part 20 limit for the
year (e.g., shallow dose equivalent to an extremity of 20
rems for both the current quarter and year to date), is the
individual unavailable for any further exposure in that
dose category for the remainder of the quarter? (3) If the
individual has received dose in excess of the "implied
annual limit" of the "old" Part 20, but less than the
respective annual limit in the revised Part 20 (e.g.,
shallow dose equivalent to the skin of 35 rems in the
current quarter and year to date), is the individual
unavailable for further exposure in that dose category for
the remainder of the year? (4) If the individual has
received a planned special exposure (PSE) at the previous
workplace in the current quarter, how should the PSE dose
be accounted for as prior occupational dose by the present
licensee under the "old" Part 20? Should the PSE dose be
subtracted from the available current quarter dose for that
dose category?
(b) In the case of a worker whose dose was monitored
earlier in the year at a licensee that has not implemented
the revised Part 20 and is now inprocessing at a licensee
that has implemented the revised Part 20: if the
individual has received recorded internal dose (in terms of
rem) or internal exposure (in terms of MPC-hrs) or internal
uptake (in terms of organ burden), how should this data be
considered with regard to revised Part 20 requirements
(i.e., TEDE, CEDE, or CDE)?
Answer: (a) (1) DDE. (2) Yes, the individual is
"unavailable for any further exposure in that dose category
for the remainder of the quarter" because the individual
has already exceeded the applicable dose limit for the
quarter. (3) The individual is unavailable for further
exposure in that dose category for the remainder of the
quarter (because the individual has exceeded the applicable
dose limit for the quarter), but is available for further
exposure in that dose category for the remainder of the
year after the end of the quarter. (4) The PSE dose should
be accounted for as occupational dose received during the
quarter and should be subtracted from the available current
quarter dose for the dose category.
b) CEDE. (Reference: 10 CFR 20.2104).