Based on ealeulstions in Appendices 8 and I, when an object is held
in a hand, a rough estinste of the retio of dose rates of beta to the basal
layer of the epidernis to that of the garra reading on a survey neter held
four inches away from an object two inches in radius (outside a general
rediation field} is 2600-5200 te 1.
(Appendix I)
Thus, if this object were
eontazinated with the sane activity per unit sres that would produces a
id-roentger whole-body gauma dose from general contamination of the area,
it would produce about 77 mr/hr gama at four {inches avay at Bl hours,
and about 200-400 reps/nour at a depth of 7 mg/en*.® Sinee the pains of
the hands have an approximate epiderzal layer of about 40
ng/on* the beta
dose to the basa? layer would be about 135-270 reys/hour.
(The time of
Fl was selected to show about the hichest magnituie of dose rates.)
If
ona assunes that the decay ts accoriizg to prhee then the total beta
dose to the basal layer of the e-idermis in the next 10 hours would be
about 255-500 reys,
whereas the above estimates do not indicate an alarming situation, a
more serious problen may come when the contamination is jut lese than that
where evacuation is indicated,
Yor exazple, the contaztnattox a the general
area tiv be five or six time: that used eas an illustration in the preceding
paragraph, without evacuation being recommended.
Thus, beta doze rates
from handling objects, especially in timcs scen after fallout, nay be high
enough to be a problem.
A simple and expedient procedure to raduce thir
factor is frequent washing ef the hands after handling objects that were ir
the fallout,
"These numbers agree fairly well with the computations in "Beta-contact
Hazards aseociated with Gammaeradiation Heasurerente of Mixed Fission
Froducts", Teresi, J.D., USERDL-383 (CONFIDENTIAL)
UNCLASSIFIED
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