25
SOURCES OF FALLOUT R4DIATION AT RONGELAP
TABLE 3 #l
Principal
Halflife
Radionuclide
aj
&b’ /$c’
years
Strontium-90
-240
c,d/
MeV
MeV
0.187
.66
ICRP-derived
limit
on da~ y
)
oral
intake
Fraction
absorbed
fr:t:u},in
f/
pCi/d
1.13
29
Plutonium-239
9860
5920
●
2470
1480
●
1.0
**
●
*
.3
24,065
S.23
-
30
●
* (60)
.001
6,537
5.24
-
30
●
*
(60)
.001
5.57
-
37
●
* (67)
.001
Americium-241
432
a’
ICRP Publication
b’
c/
Quality
factor,
20
Quality
factor,
1
d/
MeV
30
Cesium-137
a/
radiations
38.
X and gamma rays are
be less
than 10%.
(Radionuclide
omitted
whose
transformations)
total
contribution
to
dose
would
e/
Derived
from ICRP Publications
30 and 48.
The ICRP limit
on intake
for
workers
was divided
by 30 (*) to bring
the annual
committed
effective
dose-equivalent
to 170 mrem, or by 50 (**)
for 100 mrem.
The ICRP limit
includes
a factor
of 2 to prevent
any one tissue
receiving
more than 50
rem.
That factor
is unnecessary
in the present
low-dosage
case.
The
numbers in parentheses
give
the applicable
guide
without
such
correction.*
f/
ICRP Publication
Publication
48
for
30.
Supplement
transuranics.
to
●John
Part
1.
(Annals,
Vol.
3),
and
ICRP
Dunster
adds:
●pply to adults.
For children,
The intake
limits
the strontium
linit
should
be divided
by a factor
of about
3, and
those
for plutonium
and americium
by about
2. (National
Radiation
Protection
Board G 87, Aug 81.)
.
.: