1. NAME AND TITLE
IODES: A Code System for Calculating the Estimation of Dose to the World Population from Releases of Iodine-129 to the Environment.
Oak Ridge National Laboratory, Oak Ridge, Tennessee.
3. CODING LANGUAGE AND COMPUTER
Fortran IV; IBM 360/370 and 3033.
4. NATURE OF PROBLEM SOLVED
IODES is a dynamic linear compartment model of the global iodine cycle which estimates long-term doses and dose commitments to the world population from releases of 129I to the environment.
The global environment is divided into different compartments comprising the atmosphere, hydrosphere, lithosphere, and terrestrial biosphere. The global transport of iodine is described by means of time-invariant fractional transfer rates between the environmental compartments. The fractional transfer rates for 129I are determined primarily from available data on compartment inventories and fluxes for naturally occurring stable iodine and from data on the global hydrologic cycle.
The dose to the world population is estimated from the calculated compartment inventories of 129I, the known compartment inventories of stable iodine, a pathway analysis of the intake of iodine by a reference individual, dose conversion factors for inhalation and ingestion, and an estimate of the world population. For an assumed constant population of 12.21 billion beyond the year 2075, the estimated population dose commitment is 2 x 105 man-rem/Ci.
5. METHOD OF SOLUTION
IODES calculates 129I inventories in the different environmental compartments and individual and population doses as a function of time after a release to the environment by solving a set of simultaneous first-order linear differential equations using numerical methods.
6. RESTRICTIONS OR LIMITATIONS
The subroutine LSODE for solving the differential equations is provided online at the ORNL computer center and, thus, is not included in the IODES code package. If the LSODE routine is not available to the user, then an appropriate differential equation routine must be supplied by the user, and the initialization of parameters and the call statement for LSODE in the main program must be changed accordingly.
7. TYPICAL RUNNING TIME
The sample problem executed in 4 seconds on the IBM 3033.
8. COMPUTER HARDWARE REQUIREMENTS
IODES is operable on the IBM 360/370/3033 computers. It requires 96 K in the GO step.
9. COMPUTER SOFTWARE REQUIREMENTS
A Fortran H Extended compiler and two output units are required. IODES uses the LSODE differential equation solving program, but the user may substitute another routine for this purpose.
a. Included in package:
D. C. Kocher, "A Dynamic Model of the Global Iodine Cycle and Estimation of Dose to the World Population from Releases of Iodine-129 to the Environment," Environ. Int., 5, 15 (1981).
D. C. Kocher, "A Dynamic Model of the Global Iodine Cycle for the Estimation of Dose to the World Population from Releases of Iodine-129 to the Environment," NUREG/CR-0717, ORNL/NUREG-59 (November 1979).
b. Background information:
A. C. Hindmarsh, "LSODE and LSODI, Two New Initial Value Ordinary Differential Equation Solvers," ACM-Signum Newsletter, 15, 10 (1980).
11. CONTENTS OF CODE PACKAGE
Included are the referenced document (10.a) and one (1.2MB) DOS diskette which contains the source codes plus output. There is no input data; all the required data are on DATA statements in the main routine and subroutine POPULA. In addition, the iodine release data is specified in the subroutine INPUT.
12. DATE OF ABSTRACT
February 1982; updated April 1983, January 1984.
KEYWORDS: AIRBORNE; ENVIRONMENTAL DOSE; NUCLIDE TRANSPORT; RADIOACTIVITY RELEASE