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RADAR ON-LINE DATA:
On-Line Decay Data
On-Line Kinetic Data
On-Line Model Dose Factors
Occupational Dose Factors
External Point Source
Beta Dose to Skin
Immersion in Air
MEDICAL PROCEDURE DOSE CALCULATOR AND RISK LANGUAGE GENERATOR
Internal Dose System
External Dose System
External Dose Assessment
The form here is much like our standard equation, with some modifications.
Effective doses calculated at 1 m from the point source are used to calculate the dose
at other distances, assuming no shielding.
The equation is:
Another helpful resource is the Rad Pro calculator, which gives a user friendly interface for calculation of dose rates from point sources of commonly used radionuclides given the point source activity and distance from the source. Simple shielding calculations may also be performed.
Beta dose to skin
Skin dose is very difficult to measure directly and is usually estimated. The beta dose rate to the skin expressed in terms of average surface concentrations of a radionuclide on the skin gives more reliable estimates for this exposure pathway. However, the data in the literature vary as much as an order of magnitude. The dose calculated here is to the basal layer of the skin (70 micrometers in depth) due to beta rays and electrons. The gamma contribution to the dose rate is generally a few per cent. The contamination is supposed to be uniformly and thinly spread over the skin. The equation is:
Eimmersion = Effective dose from external exposure due to immersion in contaminated air [mSv],
C = Average concentration of radionuclide in air [kBq/m3],
CFimmersion = Conversion factor for radionuclide,
t = Exposure duration [h].
See the document Immersion in Air for conversion factors and example calculations. Also see the page on Internal Exposure for Occupational sources for some similar dose factors given by the IAEA.
Dose from Ground Contamination
The effective dose calculated includes the external dose and committed dose from inhalation (resuspension) resulting from remaining on contaminated ground for the period of concern – 1st month, 2nd month or lifetime (50 years). Once the radionuclide concentrations on the ground are known, the effective dose can be estimated. The equation is:
E = Effective dose from deposition for the period of concern [mSv],
Cground = Average ground concentration of radionuclide [kBq/m2],
CFground = Conversion factor: effective dose per unit deposition for radionuclide (mSv/kBq/m2). Includes external dose and committed effective dose from inhalation due to resuspension resulting from remaining on contaminated ground for the period of concern.
The equation should be calculated for each radionuclide present and the effective doses should be summed. See the document Dose from Ground Contamination for dose factors and more information.