1.5
ESTIMATE OF MAXIMAL. SKIN DOSE FROM TUE GROUND
In addition fo the total body patna dase, the very soft panima and fipher emery beta
radiation front tle plane saqgree contributed to the skin dose.
Further skut irradiation ce
sulted tram local deposits of tatlout material on the body surfiiee itself, The Latter ts impos sible to estimate, but the fornter may be roughly attempted as follows.
The bela dose rate in air ata herurht of 3 feet above the surface of in infimite plane contaminated with mixed 24-hour-old fission products is estimated to be about three times the
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DEPTH (CM)
Fig. 1.5
Comparative Depth Doses in a Phantom Man of Initial Atomic Bomb Radiation and
Radiation from ua Field of Fission Products
gamma dose. The midline gamma dose is approximately 60 per cent of the portion of the air
gamma dose due to 80 kv radiation or above. This portion in turn 1s estimated to be 90 per
cent of the gamma dose measured in air by the instrument. Thus the dose at the surface of a
phantom exposed to mixed fission product radiation from an external plane source might be
expected to be 3, (0.6)(0.9) or about six times the midline dose, if both occur at 3 feet off the
ground. Such a depth dose measurement has in fact been made experimentally at 2 previous