Dear TEd:Besides radium, there are several other methods of making "glow in the dark" watch dials. There are various non-radioactive phosphorus compounds that will glow in the dark after being exposed to light. Some modern compounds can glow for 10 to 15 hours after a relatively short exposures to bright light.
Tritium, like radium, is radioactive, but it is much safer. Tritium, a form of hydrogen, has a reasonably
short 12 year half life so it doesn't have the long term dangers that radium has, and it decays into
harmless helium. The beta particles that tritium gives off can not even penetrate the outer layer of dead skin on your body, let alone the watch crystal and watch case.