ML20147F589
| ML20147F589 | |
| Person / Time | |
|---|---|
| Issue date: | 09/15/1978 |
| From: | Levine S NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | |
| Shared Package | |
| ML20147F593 | List: |
| References | |
| RIL-035, RIL-35, NUDOCS 7810200035 | |
| Download: ML20147F589 (2) | |
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3 ^ NUCLEAR REGULATORY COMMISSION
- g WASHINGTON, D. C. 20555 k, . .., #[ SEP 151978
]0ggoc3927 1 ti i UAdc0Uggj F ROM HST Loggy WA SHI N G T Cta DC 20555 MEMORANDUM FOR: Harold R. Denton, Director Office of Nuclear Reactor Regulation TROM: Saul Levine, Director Office of Nuclear Regulatory Ruearch
SUBJECT:
RESEARCH INFORMATION LETTER # 35 SFACTOR: A COMPUTER CODE FOR CALCULATING DOSE EQUIVALENT TO A TARGET. ORGAN PER MICR0 CURIE - DAY RESIDENCE OF A RADIONUCLIDE IN A SOURCE ORGAN ,
This memorandum transmits the SFACTOR code b orf calculating S, the average dose equivalent to each of a specified list of target organs (anatomical areas being irradiated) per microcurie-day residence of a radionuclide in source organs (anatomical areas containing concentrations of the radio-nuclides) in man. This work was performed by the Health and Safety Re earch Division of the Oak Ridge National Laboratory under the direction of the Environmental Effects Research Branch of RES.
Research Request NRR-78-5, " Confirmatory Research Programs in Radiation Dose Estimation," stated that NRR staff estimations of radiation exposure to man rpquired a broadly applicable, documented, state-of-the-art dose estimation methodology. As part of its comprehensive development of com-puter codes for calculating internal doses resulting from incorporation of radionuclides, ORNL has developed the SFACTOR code. This code computes the S-factors to be used as input for the INREM II code which computes the dose equivalent to specified target organs.
The SFACTOR methodology is largely based on the work of W. Snyder et al.b It has been expanded to include components of S from alpha and spontaneous fission decay, in addition to electron and photon radiations. The S-factors are calculated for an adult with characteristics similar to those of the International Commission on Radiological Protection's " reference man."
O SFACTOR: A Computer Code for Calculating Dose Equivalent to a Target Organ per Microcurie-Day Residence of a Radionuclide in a Source Organ, ORNL/NUREG/TM-85.
NA Tabulation of Doce Equivalent per Microcurie-Day for Source and Target Organs of an Adult for Various Radionuclides, ORNL-5000.
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-l The technique for calculating absorbed fractions, embodied in the S-factor methodology, has been verified experimentally 3f. A phantom, a physical representation of a human, containing simulated skeletal components, lungs, and soft-tissue arens, was constructed. Photon emitters were distributed uniformly in selected organs of the phantom, and the absorbed fractions were measured.
The ORNL report contains a cogrl LO listing of the SFACTOR computer code written in the PL/I language with extensive commentary. A typical job control language sequence for executing the program on the IBM 360 is given as an example to the user. Sample computer output for 52 radionucli:%s is presented for an array of 24 target organs and 22 source organs.
We reconsnend that the SFACTOR code presented in ORNL/NUREG/TM-85 be used by your staff in calculating annual doses to man from routine releases of reactor effluents. If you have any questions with regard to this report, please contact Dr. Judith D. Foulke (427-4358).,
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Saul Levine, Director Office of Nuclear Regulatory Research
Enclosure:
ORNL/NUREG/TM-85 O Measurement of Absorbed Fractions for Photon Sources Distributed Uniformly in Various Organs of a Heterogeneous Phantom, ORNL-TM-4411.
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