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30 Radiation for Radionuclide Users Table 3 provides a summary of the current annual occupational dose limits for external and internal exposures. Limit Shallow Dose Equivalent, Whole-body 50 rem Shallow Dose Equivalent, Max. Extremity 50 rem Eye Dose Equivalent to the lens of the eye 15 rem Total Organ Dose Equivalent 50 rem Total Effective Dose Equivalent 5 rem Annual Occupational Dose Limits for Adult Workers In addition, internal exposure limits are addressed in the 10CFR20.1204 through the establishment of “annual limits on intake” ( ALI ). These values represent the activity which, if taken up by the body during the course of the year (in either single or multiple events), would result in the individual receiving a committed effective dose equivalent of 5 rem or a committed dose equivalent of 50 rem. Table 4 lists ALI for some commonly used radionuclides. Annual Limits on Intake for Ingestion of Selected Radionuclides Radionuclide ALI (mCI) 3 H 80 14 C 2 32 P 0.6 35 S 10 45 Ca 2 125 I 0.04 One of the significant changes in the revised 10CFR20 effective January 1, 1994 is that it requires that an individual worker’s total external and internal dose equivalents for a year be summed, and that this total be maintained <5 rem for the total effective dose equivalent (TEDE) and <50 rem for the total organ dose equivalent (TODE). Regulatory Limits for Minors Aminor is anyone under 18 years of age. The annual occupational dose limits for minors are 10% of the annual occupational dose limits specified for adult workers in section 3.2.