Quote:
HA52 wrote:
Trouble is, you cannot get those instruments rebuilt as the EPA or somebody has determined that the radium paint used is hazardous (radiation) so nobody will touch them.
They aren't at all dangerous to be around. Radium is primarily an alpha emitter, which even a sheet of paper or your skin will block. It's only hazardous to ingest (or inhale). It's the people that painted the instruments by hand that were thus exposed so the paint is no longer made to protect workers.
There are alternative luminous pigment paints that glow under UV exposure but they degrade relatively rapidly.
What is noteworthy is that the dimming of radium dials over time is not due to the decay of the radium, which has a half-life of around 1600 years. It's due to the degradation of the phosphors that the radium excites. If the paint is still intact and not flaking off, recoating with a very thin layer of the phosphors will restore luminosity for some time.
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