A simple method for assessing that internal doses are below action levels.
The accidental or deliberate dispersal of radioactive aerosols into the public environment may require urgent assessments of radiation dose to be made to aid decisions on whether treatment should be implemented, or to reassure the public that doses are acceptably low. However, rapid assessments will be difficult due to lack of information on factors such as the particle size distribution and biokinetic characteristics of the aerosol. A procedure is described that relates the amount of activity of a radionuclide in the body and excreta to time after intake for a specified dose, taking into account the likely variations in aerosol size and differences in the biokinetic behaviour of the same or different chemical forms of the radionuclide. The implementation of the procedure for an intake of caesium-137 and a dose level of 1 mSv is described and the information presented graphically. Figures for other specified dose levels can be produced by simply scaling the data by an appropriate factor. The figures can also be used to assess the most appropriate monitoring procedure and indicate the uncertainty in the assessed dose according to the parameter and parameter values used. This approach is proposed for rapid decisions on public reassurance when potentially large numbers of people are involved. It is not intended as a substitute for individual dose assessment.
Hodgson
Alan
A
HPA-RPD, Chilton, Didcot, Oxon OX11 0RQ, UK.
Stradling
Neil
N
Phipps
Alan
A
Fell
Tim
T
D001681:Biological Assay / Q000379:methods*; D006801:Humans; D008452:Maximum Allowable Concentration; D016273:Occupational Exposure / Q000032:analysis* / Q000517:prevention & control*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D011835:Radiation Protection / Q000379:methods; D017751:Safety Management / Q000379:methods / Q000458:organization & administration*