;
-438
bid,
:
The DE is obtained
ree
rem is the unit of Dose Equivalent (pe),
ey multiplying the absorbed dose in rad by modifying factors
to correct for these observed differences in the magnitude
As a consequence, the magnitude of the
TF
‘of the effect.
Ture
oO
ry
eltect will be the same for a given DE regardless of the
B.
the
radiation or the manner of radiation.
Mocdiivine factors
.
yatiation.
ctor
(QF)
which accounts
wwe ne eee
le
re
a
The
0
i
it]
-
¢
Q
tu
GS
qi
18;
»
i
yu
At the oresent time, two modifying factors are emoloyed.
for differences
ocical effects among various forms of
other
is
the
Distribution Factor
(DF)
tt
wiicsh actounts for the modification of the biological effects
é
,
when a radionuclide is nonuniformly distributed in an organ.
the DE for X-ray to bone tissue is ceternined
“ay
Or axanple,
Getermined =v
=l,wnile that for Pu-239 in the bone is
using a QF=10
(to account for the greater
iiectiveness sf alcna particl2 irradiation)
-
.
.
-
.
,
2
and a DF=5
;
(22 account Zor the sceculiar distribution of Pu in the bone)
19
.
= [==50 rem from X-rays or Pu-239 would thus incuce the same
mamser of cancers in bone but the absorbed dose from the X-reys
°
et
+
(14 be 350 vad while that From Pu-239 would be only 1 rad.