Re: Contaminated Hosp Pipes

[Wes Van Pelt <VanPeltW@IDT.NET>]

Mike Grissom wrote:
> 
> General thoughts,
> 
> Organic crud probably is accumulating iodine, and it
> is likely that corrosion centers/pits/etc. are
> also accumulating iodine.  Some of this is chemical,
> some mechanical, all of it is very difficult to
> remove in situ.  If you don't feel comfortable
> waiting for decay to happen, a good "roto-rooter"
> job likely will help some.
> 
> The only alternative that I have heard of involves
> removal of all the piping (most expensive and
> disruptive).
> 
> The drain pipe clean-out will probably reduce the
> levels, presently about 0.5 mR/h general area and 3 mR/h
> at the pipe--using the ancient exposure rate units--which presumably
> are
> the highest levels found in the surveys.
> How accessible are these pipes? If members of the general
> public can't readily get access, perhaps some labels
> warning against loitering or prolonged contact would
> suffice.  If there are areas with levels greater than
> 5 mR/h at 30 cm from the surface of the pipe, posting as a
> radiation area would be required in the USA.
> 
> For the long term, you might consider, if possible
> in your hospital, placing radionuclide therapy
> patients in rooms on lower floors.
> 
> Good Luck,
> 
> MikeG.
> 
> At 08:26 AM 6/18/97 -0500, you wrote:
> >ANY THOUGHTS ON THIS PLEASE:
> >
> >Patients receive up to 7.4GBq (200mCi) I-131 for Ca-thyroid
> radionuclide
> >therapy. This is administered on the 6th floor of our hospital.
> >
> >Excreted I-131 from these patients passes through cast ...

Good Afternoon,

I have a different idea. 

Iodine is presumably reacting with SOMETHING in the pipes. I suggest you
pour a few grams of some stable iodine (e.g., KI solution and tincture
of iodine) down the drain, thereby saturating the iodine "binding
sites." Do this a few times just prior to the patient treatment with
I-131.  Hopefully all of the binding sites will be saturated and the
I-131 will pass thru the pipes like any other material.

Wes
-- 
Wesley R. Van Pelt, Ph.D., CIH, CHP                KF2LG
President, Van Pelt Associates, Inc.     
Consulting in radiological health and safety.
mailto:VanPeltW@IDT.net        
http://shell.idt.net/~vanpeltw/index.html