SLIDE 2 Acute Exposure. In order to estimate acute exposure, meteorology and fallout dispersion models were used to calucate external exposure rate and air activity concentrations. Archival soil measurments were used to calculate surface activity levels of the iodine isotopes. The meteorology results and archival soil results were not used in the final thyroid dose estimate becuase they could not satisfy the basic criteria that new results Pygt be related to previously known facts. Two approaches 1) the estimate of I intake from urine results and 2) the estimate of particle size and nuclide composition by Japanese scientists who examined fallout collected from a Japanese fishing vessel near Rongelap, could both be related to each other and be related to the know facts about fallout arrival and duration, external exposure rate measurements and gross beta measurements. Once the nuclide composition was assessed, the composition was normalized to external exposure rate measurements. Exposure rate histories were constructed for each island. Estimates Q intake of radioiodines and radiotelluriums were normalized to the I intake estimate which was based on Rongelap urine results and related to external exposure rate. The time and mode of intake were based on diet and living pattern observations. The population mean and individual thyroid absorbed dose were based on the age and location of the exposed people. Age dependent values of thyroid absorbed dose per unit activity intake were obtained from the scientific literature. The final results were internal and external thyroid absorbed dose estimates for 251 exposed people. ACUTE EXPOSURE Meteorology Archival Soil Measurements Composition of Fallout Activity Excreted Activity Intake Absorhed Dose