Re: incident details

[AndrewsJP@AOL.COM]

In a message dated 2/5/2002 1:34:33 PM Eastern Standard Time, neildm@ID.DOE.GOV writes:



> A valid point.  I had missed that part.  Could the iridium be in a
>
> dispersible form?  The iridium sources I knew of were small metal pellets,
>
> about BB shot size.
>
>
> Dave Neil        neildm@id.doe.gov


The iridium sources I have seen manufactured are in small disks, about 1/8 inch in diameter and about 1-2 mm thick (these are approximate).  The disks are stacked in a cup, a small spring is added if needed to take up the extra space and the top is welded closed.  The source is strong and will withstand all kinds of abuse, but an electric arc can do considerable damage, perhaps enough to release one or more of the disks.  If the can is breached, there will be a release of the iridium oxide to the environment, but this material is fine and will disperse and be just ordinary contamination, not very hot spots. Chunks of iridium metal from a broken disk will be real hot spots.  These are thermally hot, by the way and will leave burn marks if they sit in one spot for a while.  Some of the burn mark may be radiation damage.  In other words, do not be stupid and pick this material up with your fingers.  The iridium contamination is very heavy an!

d will fall out and not get reentrained into the air very easily.  Any airborne iridium goes away quickly as it falls to the ground or floor or desktop or on you if you happen to be there.


Best wishes to all...




John Andrews

Knoxville, Tennessee