Patient release criteria (Reg Guide 8.39)

[Michael Burba <Michael.Burba@UC.Edu>]

We implemented the new patient release regulations on May 29, but see
a potential problem with permanent implant patients, specifically
I-125 permanent brain implants.  The new release criteria for I-125
of 1 mrem/hr at one meter is more restrictive than the old 5 mrem/hr.
 At first it was thought there would be no impact other than
occasional written instructions being triggered for greater than 0.2
mrem/hr at one meter, but a review of permanent brain cases from the
previous three years revealed four cases that exceeded the 1 mrem/hr
reading at one meter.  Our question for RADSAFERS who are familiar
with Reg Guide 8.39 is, "How are you releasing or will you release a
permanent I-125 implant patient who exceeds 1 mrem/hr at one meter?"

The option to hold them for decay (60 day half-life) seems out of the
question.  Do you consider it allowable to justify release based on
additional instructions to the patient, such as, directing a lead cap
be worn when other people are around or stay more than 4, 5, or 6
feet away from other people for some time period while decay occurs?

Any input would be greatly appreciated.

Standard disclaimer...

Michael Burba
Assistant RSO
University of Cincinnati
Michael.Burba@uc.edu