Radiation Dose to Risk Converter - HELP

(last updated 6 Oct 2004)

Contents:

Introduction

This calculator determines the health risk from a given radiation dose. For individuals, the dose can be entered as a dose, or as a dose rate plus occupancy information. For populations, the collective dose can be entered.
Note: For doses from inhalation of radon, use the Radon Individual Dose Calculator. For other dose units, see also the Unit Converter

The parameters used for the calculation can be set in the Input Data table. These parameters show reasonable initial values which can be modified as needed. There are no other hidden parameters used in the calculation. Any assumptions made for the calculations are described on this page.

Input Data

Dose
enter number (mandatory!) and select unit.

The units Sv (Sievert) and rem (R?ntgen equivalent man) and multiples are for committed effective dose.
The units Gy (Gray) and rad (R?ntgen absorbed dose) and multiples are for absorbed dose *).
The units R (R?ntgen) and C/kg (Coulomb per kilogram) and multiples are for ionic dose *).
The unit A/kg and multiples are for ionic dose rate *).
The units man-Sv and man-rem are for collective committed effective dose.

*) here applicable for external gamma exposure in air only .

Rate
select appropriate rate

Occupancy (used for rates "per hour" and "per year")
determines the time in a year a person is exposed at the given rate. It can be entered in hours per year, or in percentage of total time, or continuous exposure can be selected. Typical worktime is 2000 hours per year.
The number of years entered allows for cumulative dose calculation over the whole worklife or lifetime.

Risk Factor [1/Sv]
Fatal cancer risk per Sievert. For stochastic effects, ICRP 60 (1990) uses values of 0.04 for workers and 0.05 for the public.

Dose factor for gamma radiation [Sv/Gy] (used for units other than Sv, rem, and multiples)
Conversion factor from absorbed gamma energy in air to effective dose. UNSCEAR (2000) recommends 0.7 Sv/Gy for adults, 0.8 for children, and 0.9 for infants.