Re: ICRU Report 37, Radiological Health Handbook

["Eric L. Darois" <daroiel@naesco.com>]

     Steve
     
     The data in ICRU page 114 shows a CSDA range of 2.79E-2 g/cm^2 which 
     is 27.9 mg/cm^2 for .150 MeV.  This seem reasonable but remember that 
     this is for E(max), of which there are quite few on emmission.
     
     Eric Darois
     daroiel@naesco.com


______________________________ Reply Separator _________________________________
Subject: ICRU Report 37, Radiological Health Handbook
Author:  radsafe@romulus.ehs.uiuc.edu at Internet
Date:    10/29/96 10:37 AM


     
     
I need some help with film badge information:  
     
ICRU Report 37 lists on page 114 the average range of electrons in 
A-150 tissue equivalent plastic, a chart of these is shown in the  
Health Physics and Radiological Health Handbook page 184 - 185.
     
Please, some assistance with the interpretation of these charts as 
related to the data.  The covering on the film for our monitoring has 
a thickness of 35 mg/cm sq plastic ( I am assuming for the moment that 
it is the A-150) and the skin thickness is 7 mg/cm sq.  I am looking 
for the energy of the beta particle under which monitoring would not
be useful, feasible, practical based on this information.  We currently 
do not monitor for H-3, C-14, and S-35, however the data on page 114 of 
the ICRU document lists a .150 MeV beta as having an average range of 
0.03 mg/cm sq (rounded up).  I am confused by this information.  Does the 
factor of 8x thickness for the plastic have to do with this ?  Is there 
also a limit to the thickness of the plastic around the film to keep 
light from entering?  I am sorry for the reference to the chart for those 
of you who do not have the handbook or ICRU 37.
     
I have a query into our vendor as well.
     
Thank you.
     
steve at UMCP