If the licensee
is required to monitor under subdivisions 1 and 2 of
the licensee shall demonstrate compliance with the dose limits by summing
external and internal doses. If the licensee is required to monitor only under
subdivision 1 of
or only under subdivision 2 of
then summation is not required to demonstrate compliance with the dose limits.
The licensee may demonstrate compliance with the requirements for summation of
external and internal doses by meeting one of the conditions specified in
subsections B, C, and D of this section. The dose equivalents for the lens of
the eye, the skin, and the extremities are not included in the summation, but
are subject to separate limits.
Intake by inhalation. If the only intake of radionuclides is by inhalation, the
total effective dose equivalent limit is not exceeded if the sum of the
deep-dose equivalent divided by the total effective dose equivalent limit and
one of the following does not exceed unity:
1. The sum of the fractions of the inhalation
ALI for each radionuclide,
total number of derived air concentration-hours (DAC-hours) for all
radionuclides divided by 2,000, or
3. The sum of the calculated committed
effective dose equivalents to all significantly irradiated organs or tissues
calculated from bioassay data using appropriate biological models and expressed
as a fraction of the annual limit. For the purposes of this requirement, an
organ or tissue is deemed to be significantly irradiated if, for that organ or
tissue, the product of the weighting factors and the committed dose equivalent
per unit intake is greater than 10% of the maximum weighted value of the
committed dose equivalent per unit intake of any organ or
C. Intake by oral
ingestion. If the occupationally exposed individual also receives an intake of
radionuclides by oral ingestion greater than 10% of the applicable oral ALI,
the licensee shall account for this intake and include it in demonstrating
compliance with the limits.
Intake through wounds or absorption through skin. The licensee shall evaluate
and to the extent practical account for intakes through wounds or skin
absorption. The intake through intact skin has been included in the calculation
of DAC for hydrogen-3 and does not need to be evaluated.
12 Va. Admin. Code § 5-481-650
Virginia Register Volume 22, Issue 25, eff. September 20, 2006; amended,
Virginia Register Volume 24, Issue 18, eff. June 12, 2008; volume 32, Issue 24,
eff. August 25, 2016.
Statutory Authority: §
of the Code of Virginia.