RE: Illinois had dose limits for common projections & a std.-Reply

[Kathleen Kaufman <KKAUFMAN@dhs.co.la.ca.us>]

I can't respond to how other states came up with their values, and
California doesn't have them in our regs. I can, however, say that there
is lots of data on ESE, from both nationwide evaluations (The Conference
of Radiation Control/FDA studies), & from data gathered by multiple
staes. For example, in CA we measure ESEs during every inspection, &
that's why I can verify that a tenX variation is not unusual. All data that
I've seen has only been real world info, i.e., "what's out there," that
includes all users, & having little or nothing to do with what might be
considered "acceptable." I've been told that some years ago several
physicists tried to get that info by asking some of the "best,"  major
facilities to measure their ESEs, with the intent of trying to come up with
what one might use as a guideline. The results indicated such a wide
variance in ESEs even among these "best" facilities that guidelines
couldn't be provided on what might be considered "optimal." That
demonstrates that caution needs to be used for whatever ESEs might be
used in regulations, and also demonstrates that some facilities are able to
achieve much lower ESEs while maintaining, or even improving, image
quality.