NTS during the cascade impactor run was
measured to be 70 ug/m>.
air, and do not consider the additional
problems of resuspension of material
from contaminated clothing or the resus-
Such derived values must, of course,
be used with a great deai of discretion.
pension of material which has been trans-
They are based on simple model systems
ferred to pomes.
Healy”
which are believed to be generally conservative, but individual situations can be
imagined which could exceed the predic~
tions,
has
considered these and
other problems, and has provided tables
of "decision levels" for surface contamination levels and home transfer levels.
A
decision level is based upon National
Council on Radiation Protection and
_
Other Considerations —
Measurements (NCRP) recommended
The above calculations relate only to
the resuspended air activity in ambient
Table 152.
dose limitations,
Because the derivations
os
26
239
;
;
.
Pu, and their equivalent in soil mass
for soluble
Decision levels
based upon the “acceptable soil concentration" from Table 151.
Pathwav
Decision level
A,
Mass equivalent
Direct personal contamination
Direct inhalation®
2x10° nCi/ cm?
1x 107° g/ cm?
Direct ingestion”
0.2 nCi/ cm”
0.2 g/cm
Skin absorption®
gxio+ uci -
B.
0.8¢
Transfer (to homes) levels
Resuspension?
0.01 uCi/day
10 g/day
Direct inhalation
0.01 pCi/day
10 g/day
Direct ingestion
Skin absorption
100 ywCi/day
9.03 nCi/day
10° g/day
30 g/day
a
Ls
.
oo
3
a
.
,
"The contamination level on clothing and skin that could result in inhalation of air
:
2
at the MPC, for the public.” 6
biphe contamination level on skin or clothing that could result in ingestion of a
quantity of radioactive material equivalent to the ingestion of water at the AIPC,
.
.
.
for an individual in the public.”
26
,
"The total quantity of radioactive material maintained on the skin for 24 h/day that
could result in absorntion of 2 quantity equal tu that whien would be absorbcd from
the GI tract if water at the MPC_ for "soluble" isotopes
public were
. 1126
ineested,
*
for an individual in the
+
a
?
=
‘
mfr
7
nan
1
a
to
duc
ations
csncentr
r
air
in
red per day that could result
duphe amount transfer
in
individual
an
for
MPC_
the
at
resuspension in a medium-sized home averaging
the public. 126
I] --22