Allowable annual doses for design of radiotherapy installations

[sergio fierman <sergio@bgumail.bgu.ac.il>]

Dear radsafers,

I would like to know what are the allowable annual doses you take into 

account , for the public and for radiation workers, when designing a new 

radiotherapy installation ( dual energy linear accelerator- photons+ 

photoneutrons). Till now I used 5 mSv/Y for controlled areas and 1 mSv/y 

for public areas. The authorities in my country are now questioning these 

values. Are there some sound justifications  for even lowering these limits?

Can somebody tell me in what national regulations are there specific 

recommendations on doses for SHIELDING DESIGN of medical installations?

It's my understanding that the rad.prot. experts didn't intend to require 

population doses for all the walls of the installation!

Another relevant question is : what the  authorities can require for an 

EXISTING installation in which the linear accelerator will be replaced?


Yours sincerely


Sergio
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 Sergio Faermann Ph.D.                      Tel: 972 - 7 - 400682
 Chief Medical Physicist                    Fax: 972 - 7 - 232336      
 Institute of Oncology                      E-mail: sergio@bgumail.bgu.ac.il
 Soroka Medical Center
 P.O.B 151 Beer-Sheva 84101
 ISRAEL
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