Re: This will work
Tritium is still allowed for instruments, though it has to be contained in a glass cylinder that's glued to the dial and hands instead of being painted directly on - to save watch repairers from inhaling it in dust ( the radioactivity tended to weaken the glue, resulting in a powder that clogged gears and could be inhaled ). It only has half life of about 12 years though (compared to a thousand years plus for radium).
In any case, aerospace and military applications can be made exempt from certain legislation - such as using lead-based solder, for example.
Biting the hand that feeds IT
