t
tae
methods of estimating gama doses
since there are uncertainties in
evaluating the hasards of seach transitory air concentrations as
experisanesd
series indicates that the external gawa hesard {s more liniting than the
dan
hy
from fallout, and sinee the preponderance of evidence from past nuclear test
{nhalstion one, 1t vas recomended in the Jasuary 20, 1954 meeting to
strike from the record the past recommendations for maximum peruissible
alr concentrations.
It was recomended thet an air monitoring program be
eontinued fer documentary purposes and for vhatever value the data might
{
tional knowledge.
°
.
& further éiscussien ef the single particle problea may be nade.
In arriving st the recommendation °... nor is it desirable thet any indivi~
dual particle in this size range have activity greater than 1072 xicrocuries
@alculated four hours after the blast® a computation was made that the aver-
age radiation dose from such « particle to a sphere one-half a millineter
bh
. See ‘
have in the future when new analyses might be made in the light of addi-
{n radius would be 385 reps.* However, the conclusions may be misleading.
“In the case of a single particle, relatively large doses are
near the particle and small doses at a greater distance,
one possible estinate of this phenoxenon.
many and difficult to svaluate.
éelivered
Appendix 1 suggests
The peraneters involved here are
Por exaaple, how long vill a particle rezain
in one place in the lung and what dose will be delivered during that tine?
It has been suggested** that ta the wpper respiratory passage 20-ricron
dianeter particles are the upper limit of sise for deposition and that "Cilla
®Himutes, Nesting of Comittee to Consider the Feasibility and Conditions Por
@ Preliminary Radiologic Safety Shot for J.
@. L.A.S.L. May 2] and 22, 1951.
engu-33068, 4 status report. Sept. 15, 1954. (COXFIDENTIL).
‘
oe
pe
ses
mrert