Current through Register Vol. 43, No. 52, December 26, 2024
(a) When
assessing the dose used to determine compliance with occupational dose
equivalent limits, each licensee or registrant shall, when required pursuant to
K.A.R. 28-35-217b, take suitable and timely measurements of any of the
following:
(1) Concentrations of radioactive
materials in the air in work areas;
(2) quantities of radionuclides in the body;
(3) quantities of radionuclides
excreted from the body; or
(4) any
combination of the measurements specified in paragraphs (a)(1) through (3).
(b) Unless respiratory
protective equipment is used, as specified in K.A.R. 28-35-212g, or the
assessment of intake is based on bioassays, the licensee or registrant shall
assume that an individual inhales radioactive material at the airborne
concentration in which the individual is present.
(c) If 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 or registrant
may perform the following:
(1) Use that
information to calculate the committed effective dose equivalent, and if used,
the licensee or registrant shall document that information in the individual's
record;
(2) before approval of the
secretary, adjust the DAC or ALI values to reflect the actual physical and
chemical characteristics of airborne radioactive material; and
(3) separately assess the contribution of
fractional intakes of class D, W, or Y compounds of a given radionuclide to the
committed effective dose equivalent.
(d) If the licensee or registrant chooses to
assess intakes of class Y material using the measurements given in paragraph
(a)(2) or (3), the licensee or registrant may delay the recording and reporting
of the assessments for up to seven months, unless otherwise required by K.A.R.
28-35-229a or K.A.R. 28-35-230a, in order to make additional measurements basic
to the assessments.
(e) If the
identity and concentration of each radionuclide in a mixture are known, the
fraction of the DAC applicable to the mixture for use in calculating DAC-hours
shall be either of the following:
(1) The sum
of the ratios of the concentration to the appropriate DAC value, from appendix
B published in "appendices to part 4: standards for protection against
radiation," as adopted in K.A.R. 28-35-135a, for each radionuclide in the
mixture; or
(2) the ratio of the
total concentration for all radionuclides in the mixture to the most
restrictive DAC value for any radionuclide in the mixture.
(f) If the identity of each
radionuclide in a mixture is known but the concentration of one or more of the
radionuclides in the mixture is not known, the DAC for the mixture shall be the
most restrictive DAC of any radionuclide in the mixture.
(g) If a mixture of radionuclides in air
exists, a licensee or registrant may disregard certain radionuclides in the
mixture if all of the following conditions are met:
(1) The licensee or registrant uses the total
activity of the mixture in demonstrating compliance with the dose limits in
K.A.R. 28-35-212b and in complying with the monitoring requirements in K.A.R.
28-35-217a (d).
(2) The
concentration of any radionuclide disregarded is less than 10 percent of its
DAC.
(3) The total concentration
of all of the radionuclides disregarded in the mixture does not exceed 30
percent.
(h) When
determining the committed effective dose equivalent, the following information
may be considered.
(1) In order to calculate
the committed effective dose equivalent, the licensee or registrant may assume
that the inhalation of one ALI, or an exposure of 2,000 DAC-hours, results in a
committed effective dose equivalent of 0.05 Sv (5 rem) for radionuclides that
have their ALIs or DACs based on the committed effective dose equivalent.
(2) For an ALI and the associated
DAC determined by the nonstochastic organ dose limit of 0.50 Sv (50 rem), the
intake of radionuclides that would result in a committed effective dose
equivalent of 0.05 Sv (5 rem), which is the stochastic ALI, is listed in
parentheses in appendix B, table I in "appendices to part 4: standards for
protection against radiation," as adopted in K.A.R. 28-35-135a. The licensee or
registrant may, as a simplifying assumption, use the stochastic ALI to
determine the committed effective dose equivalent. However, if the licensee or
registrant uses the stochastic ALI, the licensee or registrant shall also
demonstrate that the limit in K.A.R. 28-35-212a(a)(1) (B) is met.
