Q: "Tandetron" accelerator and regs

["M. Woo" <melissa@zelda.ehs.uiuc.edu>]

A group of researchers here just bought a used 1.7 MV Tandetron tandem 
accelerator which is presently configured to accept either a hydrogen ion 
or helium ion source.  Expected beam performance will be:

5.1 MeV He++, 1 uA at high energy end
3.4 MeV H+, 30 uA at high energy end.

The configuration of the accelerator is such that the operating console 
is movable and is at this time located right next to the target end, but 
can be moved down to the source end as well.

Here's the problem... the regs here (Illinois is an agreement state) say 
that for particle accelerators, all entrances to the accelerator room 
must be equipped with two personnel interlocks.

But hm, the shielding and design of the accelerator is *supposedly* such 
that the accelerator can be safely operated from within the same room.  
This however throws the whole idea of double-interlocked doors into the 
air; what would be the point?

So, I know there should be several of these units around, and I assume 
that other states have regs similar to ours.  How is this being handled 
elsewhere?  Are other regulatory agencies allowing the operation of the 
console in the same room, and are you being held to the double-interlock 
requirement?

Thanks in advance!

--
 Melissa Woo, Health Physicist                       | m-woo@uiuc.edu
 University of Illinois at Urbana-Champaign          | office 1.217.244.7233
 DEHS, MC-225, 101 S. Gregory St., Urbana, IL  61801 | fax    1.217.244.6594
 http://www.uiuc.edu/ph/www/m-woo                    |