X-ray equipment

Audrey Yardley-Jones <conservation [at] museumsalberta__ab__ca> writes

>I have been contacted by a small, community museum that has an
>"x-ray shoe machine" in their collection and would like to know what
>its hazards are and whether they need to deaccession it.

I have only heard about these machines but based on descriptions and
the kV needed to penetrate the human body the kV would have been on
the lower end (although not acceptable by today's standards).  But,
this radiation would only be emitted with an applied current...ie
they are x-ray machines (as I understand them) not isotopic sources.
Unless there is some other radioactive component (radium dial?) I
suspect there is no radiation risk (you can also check it with a
Geiger counter to be sure). I can't comment on PCB's but I found
some info in the book Naked to the Bone, Medical Imaging in the 20th
Century, by B. Kevles. This might help with understanding the
system.

She states that gas tubes were replaced by "Coolidge tubes" around
the time of WWI (they changed AC to DC power for quieter operation).
Coolidge tubes could be run off of engines for wound diagnostics in
the field.  After the war a large number of these became available
and the shoe fluoroscope was one offshoot.  One model was the
Foot-O-Scope marketed by the United Shoe Machinery Corporation. The
machines remained a part of shoe stores for another 40 years.
Curiously they had buttons marked "Man", "Woman" and "Child" but the
dosages were all equal! Who knows how much radiation people were
exposed to, but they got well-fitting shoes.
Hope this helps,

Jeff Maish

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                  Conservation DistList Instance 13:30
               Distributed: Wednesday, November 17, 1999
                       Message Id: cdl-13-30-005
                                  ***