Document Details

Estimates of Dose Due to Noble Gas Releases from the Three Mile Island Incident Using the AIRDOS-EPA Computer Code
Subject Terms:
AIRDOS-EPA computer code; Task Group, health physics; dose, estimates, gas, ORNL; dosimetry, nuclear reactor; meteorological data; release, Three Mile Island
Document Location:
DOE INFORMATION CENTER 1 Way, Oak Ridge, TN 37831; Eva Butler; Phone: 865-241-4780; Toll-Free: 800-382-6938, Option 6; FAX: 865-574-3521; Email:
Document Categories:
Health, Safety and Environment\Public Health and Safety; Science and Technology\Instruments and Equipment; Reactors\General
Document Type:
Publication Date:
1980 Dec 31
Declassification Status:
Never classified
Document Pages:
Accession Number:
Document Number(s):
Originating Research Org.:
Oak Ridge National Laboratory
OpenNet Entry Date:
1998 Jun 16
In response to a request from the Task Group on Health Physics and Dosimetry of the President's Commission on the Accident at Three Mile Island (TMI), radiation doses to persons living within 80 km (50 miles) of the reactor were estimated using the AIRDOS-EPA computer code. Hourly radionuclide release and corresponding meteorological data were supplied by the Task Group. From these data the degree of dispersion of the total release into each of 16 wind direction sectors was calculated. The average fractions of the total release of the noble gases 133-Xe, 135-Xe, and 88-Kr (the major dose contributors) were estimated to be 95 percent, 4 percent, and 1 percent, respectively. The release period used in our calculations was from March 28 through April 15, 1979 (19 days.) Our original population dose estimate to the total body of 4 person-Sv was based on a 22.5 sector-averaged Gaussian plume atmospheric dispersion model calculation assuming an elevated release. This dose estimate is about a factor of 7 lower than the dose estimated by the Task Group (neglecting shielding effects) based on 20 thermoluminescent dosimeter (TLD) measurements (28 person-Sv). Comparison of predictions by our model with the individual TLD measurements revealed that use of a ground-level release resulted in better agreement with the TLDs than did use of an elevated release. Assuming a ground-level release, our revised population dose was 15 person-Sv, which is within a factor of 2 of the Task Group estimate. The highest population dose estimate for the TMI incident is about 1 percent of that expected annually from natural background for the same population (2700 person-Sv). It has been estimated that this dose it too small to result in any detectable physical health impact. A figure of the Three Mile Island Nuclear Station, and tables are included.

<< Return to Search Results