| (2) The licensee shall use, to the extent practicable,
procedures and engineering controls based upon sound radiation protection
principles to achieve occupational doses and public doses that are
as low as is reasonably achievable (ALARA).
(3) The licensee shall, at intervals not to exceed
12 months, ensure the radiation protection program content and implementation
is reviewed. The review shall include a reevaluation of the assessments
made to determine monitoring is not required in accordance with subsection
(q)(1) and (3) of this section in conjunction with the licensee's
current operating conditions.
(4) To implement the ALARA requirement in paragraph
(2) of this subsection and notwithstanding the requirements in subsection
(n) of this section, a constraint on air emissions of radioactive
material to the environment, excluding radon-222 and its daughters,
shall be established by licensees such that the individual member
of the public likely to receive the highest dose will not be expected
to receive a total effective dose equivalent (TEDE) in excess of 10
millirems (mrem) (0.1 millisievert (mSv)) per year from these emissions.
If a licensee subject to this requirement exceeds this dose constraint,
the licensee shall report the exceedance as required in subsection
(yy) of this section and promptly take appropriate corrective action
to ensure against recurrence.
(5) If monitoring is not required in accordance with
subsection (q)(1) and (3) of this section, the licensee shall document
assessments made to determine the requirements of subsection (q)(1)
and (3) of this section are not applicable. The licensee shall maintain
the documentation in accordance with subsection (rr)(5) of this section.
(f) Occupational dose limits for adults.
(1) The licensee shall control the occupational dose
to individuals, except for planned special exposures in accordance
with subsection (k) of this section, to the following dose limits.
(A) An annual limit shall be the more limiting of:
(i) the total effective dose equivalent being equal
to 5 rems (0.05 Sv); or
(ii) the sum of the deep dose equivalent and the committed
dose equivalent to any individual organ or tissue other than the lens
of the eye being equal to 50 rems (0.5 Sv).
(B) The annual limits to the lens of the eye, to the
skin of the whole body, and to the skin of the extremities shall be:
(i) a lens dose equivalent of 15 rems (0.15 Sv); and
(ii) a shallow dose equivalent of 50 rems (0.5 Sv)
to the skin of the whole body or to the skin of any extremity.
(2) Doses received in excess of the annual limits,
including doses received during accidents, emergencies, and planned
special exposures, shall be subtracted from the limits for planned
special exposures that the individual may receive during the current
year and during the individual's lifetime. See subsection (k)(6)(A)
and (B) of this section.
(3) When the external exposure is determined by measurement
with an external personal monitoring device, the deep-dose equivalent
shall be used in place of the effective dose equivalent, unless the
effective dose equivalent is determined by a dosimetry method approved
by the agency. The assigned deep dose equivalent shall be for the
portion of the body receiving the highest exposure. The assigned shallow-dose
equivalent shall be the dose averaged over the contiguous 10 square
centimeters (cm2 ) of skin receiving the
highest exposure.
(4) The deep dose equivalent, lens dose equivalent
and shallow dose equivalent may be assessed from surveys, or other
radiation measurements for the purpose of demonstrating compliance
with the occupational dose limits, if the individual monitoring device
was not in the region of highest potential exposure, or the results
of individual monitoring are unavailable.
(5) Derived air concentration (DAC) and annual limit
on intake (ALI) values are specified in Table I of subsection (ggg)(2)
of this section and may be used to determine the individual's dose
and to demonstrate compliance with the occupational dose limits. See
subsection (rr) of this section.
(6) Notwithstanding the annual dose limits, the licensee
shall limit the soluble uranium intake by an individual to 10 milligrams
(mg) in a week in consideration of chemical toxicity. See footnote
3 of subsection (ggg)(2) of this section.
(7) The licensee shall reduce the dose that an individual
may be allowed to receive in the current year by the amount of occupational
dose received while employed by any other person. See subsection (j)(4)
of this section.
(g) Compliance with requirements for summation of external
and internal doses.
(1) If the licensee is required to monitor in accordance
with both subsection (q)(1) and (3) of this section, the licensee
shall demonstrate compliance with the dose limits by summing external
and internal doses. If the licensee is required to monitor only in
accordance with subsection (q)(1) of this section or only in accordance
with subsection (q)(3) of this section, 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 in accordance with paragraphs (2) - (4) of this subsection.
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.
(2) 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:
(A) the sum of the fractions of the inhalation ALI
for each radionuclide; or
(B) the total number of derived air concentration-hours
(DAC-hours) for all radionuclides divided by 2,000; or
(C) the sum of the calculated committed effective dose
equivalents to all significantly irradiated organs or tissues (T)
calculated from bioassay data using appropriate biological models
and expressed as a fraction of the annual limit. For 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,
wT , and the committed dose equivalent,
HT,50 , per unit intake is greater than
10% of the maximum weighted value of HT,50 ,
that is, wT HT,50 ,
per unit intake for any organ or tissue.
(3) If the occupationally exposed individual 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.
(4) 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 or accounted
for in accordance with this paragraph.
(h) Determination of external dose from airborne radioactive
material.
(1) Licensees shall, when determining the dose from
airborne radioactive material, include the contribution to the deep
dose equivalent, eye dose equivalent, and shallow dose equivalent
from external exposure to the radioactive cloud. See footnotes 1 and
2 of subsection (ggg)(2) of this section.
(2) Airborne radioactivity measurements and DAC values
shall not be used as the primary means to assess the deep dose equivalent
when the airborne radioactive material includes radionuclides other
than noble gases or if the cloud of airborne radioactive material
is not relatively uniform. The determination of the deep dose equivalent
to an individual shall be based upon measurements using instruments
or individual monitoring devices.
(i) Determination of internal exposure.
(1) For purposes of assessing dose used to determine
compliance with occupational dose equivalent limits, the licensee
shall, when required in accordance with subsection (q) of this section,
take suitable and timely measurements of:
(A) concentrations of radioactive materials in air
in work areas;
(B) quantities of radionuclides in the body;
(C) quantities of radionuclides excreted from the body;
or
(D) combinations of these measurements.
(2) Unless respiratory protective equipment is used,
as provided in subsection (x) of this section, or the assessment of
intake is based on bioassays, the licensee shall assume that an individual
inhales radioactive material at the airborne concentration in which
the individual is present.
(3) When specific information on the physical and biochemical
properties of the radionuclides taken into the body or the behavior
of the material in an individual is known, the licensee may:
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