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Greetings! I am dipping my toe into shielding requirements for theranostics. One of the hot new isotopes of course is Pb-212. I had looked at its decay chain a while back and saw a rather high-yield MeV emission from its daughter Tl-208 and</div>
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<div dir="ltr"><div>Greetings!</div><div><br></div><div>I am dipping my toe into shielding requirements for theranostics. One of the hot new isotopes of course is Pb-212. I had looked at its decay chain a while back and saw a rather high-yield MeV emission from its daughter Tl-208 and figured we could forget about a reasonable amount of lead. We'd have to use time and distance. HOWEVER today, I thought to look at the Smith and Stabin paper that lists 1000+ isotopes with their gamma rate factors and HVL, etc. data. Pb-212 is listed as having an HVL of only 0.756 mm Pb, which is about 1/7th the HVL they list for F-18! I understand that F-18 is almost 100% positron decay, but I still find this difference in HVL incredible.</div><div><br></div><div>Before going down a wild rabbit hole, I figured I'd probe the list for any other insights into Pb-212. We are starting a clinical trial soon using it, and I've been tasked with writing up a Radiation Safety SOP. In addition, we are doing a reno of one of our NM departments, and they would like to add dedicated theranostic injection rooms... so trying to see what kind of lead to put in the walls. (It's truly an impossible task, but I'm giving it my "college try.")</div><div><br></div><div>Many, many thank yous in advance.</div><div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><p style="text-align:left"><font face="tahoma, sans-serif"><span style="font-size:small">Gretchen R. Bell, M.S., DABR</span><br><font size="2">Diagnostic Imaging Physicist</font><br><font size="2">Ochsner Medical Center</font><br><font size="2">(504)842-8506</font></font></p>
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