Re: Ion chamber versus GM

[Bob Carlson <carlson@en.com>]

Chris Alston wrote:
> 
> If the 450P isn't a "radiation detection survey instrument", what, in
> heaven's name, is it? 

By conversation and discussion with NRC personnel (and I used to be a
Victoreen Regional Manager) I can tell you that the NRC considers a
radiation "detection" intstrument to be a G-M detector and that they
consider a radiation "measurement" device to be that of an ion chamber
device.  

Also, the linearity that you speak of is in terms of response and not
that of energy response which is how the NRC based their definitions. 
that and the fact that to really "measure" a radiation field (such as a
beam, therapy or diagnostic, etc) one uses an ion chamber.