NCRP-147 Shielding Models 147 Shielding Models - Radiation ...
NCRP-147 Shielding Models 147 Shielding Models - Radiation ...
NCRP-147 Shielding Models 147 Shielding Models - Radiation ...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Scatter <strong>Radiation</strong><br />
• Same theory as old <strong>NCRP</strong>-49<br />
K<br />
– scatter fraction data of Kelley & Trout reevaluated<br />
by Simpkin & Dixon (Health Phys 1998)<br />
– pri ib beam area F (cm 2 ) measured at pri idistance d F<br />
conveniently taken as image receptor area @ SID<br />
– explicitly itl show kVp dependence d and sum over<br />
workload distribution to yield shielded scatter<br />
kerma<br />
S<br />
−6<br />
a′<br />
× 10 K ( ) ( )<br />
,<br />
1 W<br />
kVp W kVp F<br />
( x θ ) =<br />
∑<br />
B<br />
( x,<br />
kVp<br />
)<br />
2 2<br />
d<br />
d<br />
kVp<br />
S<br />
F<br />
24
Change language