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APPENDIX
B
Appendix B is an abridged version of the Appendix B to "10
CFR
Part 20" For
the Table 1, 2 or 3 values for any radioisotopes which are not listed in
this Appendix, contact the Office of Environmental Health and Safety.
Table 1: ANNUAL LIMITS ON INTAKE (ALIs) AND DERIVED
AIR CONCENTRATIONS (DACs) OF RADIONUCLIDES FOR OCCUPATIONAL EXPOSURE
For each radionuclide, Table 1 indicates the chemical form which is to be used
for selecting the appropriate ALI or DAC value. The ALIs and DACs for inhalation
are given for an aerosol with an activity median aerodynamic diameter (AMAD)
of 1 mm and for three classes (D, W, Y) of radioactive material, which refer
to their retention (approximately days, weeks or years) in the pulmonary region
of the lung. This classification applies to a range of clearance half-times
of less than 10 days for D, for W from 10 to 100 days, and for Y greater than
100 days. The class (D, W, or Y) given in the column headed "Class" applies
only to the inhalation ALIs and DACs given in Table 1, columns 2 and 3.
Table 2: EFFLUENT CONCENTRATIONS
Table 2 provides concentrations limits for airborne and liquid effluents released
to the general environment.
Table 3: CONCENTRATIONS FOR RELEASE TO SEWERAGE
Table 3 provides concentration limits for discharges to sanitary sewer systems.
Page B.2, which comes directly from Appendix B to "10
CFR Part 20",
provides additional information about the derivation and use of Tables 1, 2,
and 3.
FOOTNOTES:
1. "Submersion" means that values given are for submersion
in a hemispherical semi-infinite cloud of a airborne material.
2. These radionuclides have radiological half-lives of less than 2 hours.
The total effective dose equivalent received during operations with
these radionuclides might include a significant contribution from external
exposure.
The DAC values for all radionuclides, other than those designated Class "Submersion," are
based upon the committed effective dose equivalent due to the intake
of the radionuclide into the body and do NOT include potentially significant
contributions to dose equivalent from external exposures. The Authorized
User may substitute 1E-7 µCi/ml for the listed DAC to account
for the submersion dose prospectively, but should use individual monitoring
devices or other radiation measuring instruments that measure external
exposure to demonstrate compliance with the limits. (See Section 8.3.3
and 10 CFR 20.1203)
3. For soluble mixtures of U-238 and U-235 in air, chemical toxicity
may be the limiting factor (see 10 CFR 20.1201(e) for more details.)
NOTE:
If the identity and concentration of each radionuclide in a mixture
are known, the limiting values should be derived as follows: determine,
for
each radionuclide in the mixture, the ratio between the concentration
present in the mixture and the concentration otherwise listed in this
Appendix
or in Appendix B to 10 CFR 20.1001-20.2401 for the specific radionuclide
when not in a mixture. The sum of such ratios for all of the radionuclides
in the mixture may not exceed "1" (i.e., "unity").
Example: If radionuclides "A," "B," and "C" are
present in concentrations CA, CB and CC, and if the applicable DACs
are DACA, DACB, and DACC, respectively, then the concentrations shall
be limited
so that the following relationship exists::
CA..........CB..........CC
------ + ------ + ------ < 1
DACA.....DACB......DACC
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