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TABLE 23-3. AVERAGE ANNUAL OCCUPATIONAL EFFECTIVE DOSE EQUIVALENTIN THE UNITED STATESAverage annual totaleffective dose equivalentUranium miners·Nuclear power operations bAirline crewsDiagnostic radiology and nuclear medicine techsRadiologists12.06.01.71.00.71,20060017010070Adapted for measurably exposed personnel from National Council on Radiation Protection andMeasurements. Exposure of the U.S.population from occupational radiation. NCRPreport no. 101.Bethesda, MD: National Council on Radiation Protection and Measurements, 1989.·Includes 10 mSv (1 rem) from high LET(a) radiation.blncludes 0.5 mSv (50 mrem) from high LET(a) radiation.LET,linear energy transfer.average annual effective dose equivalents to airline crews, who are not regarded as radiationworkers, ~1.7 mSv/year (170 mrem/year), typically exceed the annual effectivedose equivalents to diagnostic radiology and nuclear medicine personnel.Another way to assess the impact on human health from population radiation exposuresis to evaluate the average effective dose equivalent and the size of the exposedpopulation. The product of these two factors is the collective effective dose equivalent,expressed in person-sieverts (person-Sv or person-rem). Table 23-4 shows an estimateof the U.S. population collective effective dose equivalent from natural backgroundand technologic radiation sources.Table 23-5 shows the collective effective dose equivalent for some occupationallyexposed groups. Although uranium miners have some of the highest averageindividual exposures, they have among the lowest collective effective dose equivalentdue to the relatively small size of the work force compared to other occupa-TABLE 23-4. SUMMARY OF THE ANNUAL COLLECTIVE EFFECTIVE DOSEEQUIVALENT FROM ALL SOURCES IN THE UNITED STATESPerson-Sv/yr Person-rem/yr % TotalRadon 460,000 46,000,000 -55Natural background (excluding radon) 230,000 23,000,000 -28Medical radiation 123,000 12,300,000 -15Enhanced natural sources (consumer products, 20,000 2,000,000