RE: Shielding Calculations

["Scott Richards" <sr996@poppa.fab.albany.edu>]

Thanks for the input and I do have the NBS handbook 111 and ANSI 
N43.3-1993 .  The problem that worries me about this unit is that it 
is an open unit and that the hours of expected use is extremely high 
(mA-min/wk). I have several other XRD units here but nothing like 
this unit.  I recommended that we put an enclosure around the source 
but the PI said that it was not possible due to the nature of the 
protocol. It will be in an open room that is devided by a wall with 
windows in it. 

My calculations show minimal need for shielding as long as we are 
only seeing the soft 8 keV x-rays but if we will be seeing the 55 kVp 
we may run into a problem with the workload.

> From:          "Lindsey, Gary" <lindseg@wrigem.wpafb.af.mil>
> To:            "'Scott Richards'" <SR996@poppa.fab.albany.edu>
> Subject:       RE: Shielding Calculations
> Date:          Thu, 14 Nov 96 07:09:00 PST

> 
> Most diffraction units I have surveyed don't really need a lot of   
> additional shielding.  Your message doesn't mention it, but most have an   
> enclosure around the unit that is normally sufficient to attenuate any   
> radiation leakage.  Even at that, I have performed some surveys inside   
> the enclosure, with shutters open and found little radiation above   
> background.
> 
> One publication I have is NBS Handbook 111 "Radiation Safety for X-Ray   
> Diffraction and Fluorescence Analysis Equipment".  It's also designated   
> American National Standard N43.2-1977.  The copy I have is old, revised   
> 1977, and I don't know if a newer version is available.
> 
> All this being said, the only incident of radiation exposure I have had   
> here in the past eight years involved a Ph.D. late on a Friday afternoon   
> that was in a hurry and didn't bother to close the shutter before trying   
> to realign a sample on a diffraction unit.  Fortunately, only minor   
> radiation burn to a finger.
> 
> Might want to find a film called "Double Edge Sword".  Safety training   
> for x-ray diffraction operation.  It's 24 minutes long and was produced   
> in 1976 by BRH and NBS.
> 
> This should get you started and I'm sure you will be getting additional   
> and more current assistance from Radsafe.
> 
> Gary Lindsey
> Radiation Safety
> Wright-Patterson AFB, OH
> lindseg@wrigem.wpafb.af.mil  
> 
> 
Scott Richards, RRPT
Radiation Safety Officer
University at Albany, SUNY
1400 Washington Ave., Chemistry B-73
Albany, NY  12222
518-442-3497
Fax: 518-442-3783
SR996@poppa.fab.albany.edu