That's an old shoe-fitting x-ray machine, which was a popular gimmick in shoe stores in the late 1940s and early 1950s. The machine went the way of the dodo bird when it was discovered that the hazards from x-ray radiation weren't worth the proper fit of shoes:
The primary component of a shoe-fitting x-ray unit was the fluoroscope which consisted essentially of an x-ray tube mounted near the floor and wholly or partially enclosed in a shielded box and a fluorescent screen. The x-rays penetrated the shoes and feet and then struck the fluorescent light. This resulted in an image of the feet within the shoes. The fluorescent image was reflected to three viewing ports at the top of the cabinet, where the customer, the salesperson, and a third person (your mother?) could view the image at the same time.
The radiation hazards associated with shoe fitting x-ray units were recognized as early as 1950. The machines were often out of adjustment and were constructed so radiation leaked into the surrounding area.
This particular unit, however, was in operation in a shoe store in West Virginia as late as 1981: Link - Thanks choggie!
When the Mutually-Assurred Destruction (or MAD) rational of nuclear deterrence was formulated, then-Federal Defense Secretary Robert McNamera had a study done with the then-current measurement used for the megatonnage needed to effectively whipe out the human race from radiation exposure, and it was determined in 1962 that a fatal dose would be an arbitrary 40R.
(the context would be an exchange of 200 missiles, whose combined megatonnage would equal a mean dispersion of about 800R across and throughout the planet, within a variety of time models then calibrated to where various U.S. and U.S.S.R. targets would have been liquidated, wind patterns, "leakage," missiles not reaching their targets, etc.; as a species cockroaches still thrive in an 800R atmosphere, so life would not end, jus' revert to an earlier experience in a post-nuclear world).
So from the information provided above, one could surmise that an individual could conceivably receive an over-the-top, fatal dosage of radiation with just two exposures from these machines.
That they should be historic items on display, demonstrating through such display a failure of technology saved and not destroyed as a technological witness of that failure, we as a species need to look at the amount of accumulative radiation that has been contributed by human arrogance, and not pass off that contribution as naturally-bourne radon, which does exist, but not as the background radiation which in actuality has been caused by Humanity, which irradiates us all, "Now, More Than Ever."