beta shield sources

[NICHOLAS THEODORAKIS]

In article <rjordan-2510951356100001 at linus.radonc.washington.edu>,
Rob Jordan <rjordan at tezcat.com> wrote:
>Can anyone email me some companies/catalog/etc. phone numbers that have
>good selections of beta shielding devices.  I'm looking primarily for
>boxes, containers, shields, etc. of various sizes, but every <insert
>common lab supply catalog here> catalog that I've looked in has a page or
>two at best.  I mean something like Acme Radiation Saftely Supply would be
>perfect.
>
>Thanks-
>Rob      rjordan at u.washington.edu

Well, I don't have a recommendation (many lab supply vendors sell them),
but I do have an observation that I hope will generate some discussion. 
We have some plastic beta shields from Owl Scientific around the lab; 
when we were doing some rad. surveys with a monitor that has probes for
both beta- and gamma rays, we noticed that 32P kept behind the shield
generated a lot of bremstrallung (spelling?) gamma radiation when it hit 
the plastic (which did block the betas, BTW).  I almost think it would 
safer not to use the shield.  Has anybody else noticed this with their 
beta-shields?  Any comments?

Nick

-- 
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
			Nick Theodorakis
			ntheo at welchlink.welch.jhu.edu
			Johns Hopkins Medical School, Baltimore, MD