Marshall Islands Dose Assessment and Radioecology Program
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Marshall Islands :: Calculate Your External Gamma Dose

Begin Session: External Dose Calculator
External gamma radiation from nuclear test-related fallout contamination in the Marshall Islands is dominated by exposure to residual cesium-137 contamination in soil. The Marshall Islands Program periodically conducts field surveys of islands and atolls and deploys in-situ gamma spectrometers in order to measure external gamma dose rate contributions from cesium-137 at 1-meter above the ground. The data developed on this web site are largely derived from static dose rate measurements taken directly from Model 935 Surveillance and Measurement (SAM) systems supplied by Berkeley Nucleonics, BNC with no further corrections applied. Detailed analyses of these data under more standard convention and practice with applicable corrections will be reported separately.
The look-up function on this web site gives the external dose in units of mSv.
For comparative purposes, we also provide a nominal annual external dose estimate (mSv per year) for a full year of occupancy on the main residence islands. These estimates are based on observation of people's living habits and use a normalized average distribution of people's time in various locations on the island, e.g., percentage of time spend in the interior of house, around village and housing area, on the beach or lagoon, and/or on the interior of the island. The external dose component normally contributes about 10-15% of the total nuclear test-related dose with the most significant fraction coming from ingestion of cesium-137 from consumption of native tree crops such as coconut, breadfruit and Pandanus fruit.
1 millisievert (1 mSv) = 100 millirem (1 mrem)
Click "Begin Session" to start calculating your external gamma dose. To calculate your dose, you will need to select a visited or potentially visited area, enter the hours spent in various locations within that area, and the date visited. You can select multiple areas on multiple islands. Your calculated dose for each area will be stored until your session ends.

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Last Modified: 25-AUGUST-2020 | LLNL-WEB-643799 | Contact Us
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