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I've read that these used Radium on dial and hands. If true, something to be aware of when opening up. Dont want to breathe any of it in.

Roland Ranfft is offering two re-luming pastes with excellent instructions on their use (as in Mark's video). One is based on the phosphor Zinc Sulphide (ZnS) , the other on Luminova. http://www.ranfft.de/cgi-bin/bidfun.cgi?10&ranfft&b7&1usem&1456959600 http://www.ranfft.de/cgi-bin/bidfun.cgi?10&ranfft&b7&1usem&1456959601 These will glow for a few hours after exposure to sunlight (phosphorescence). The early Radium luminous dials and hands glowed continuously due to the very long lifetime Alpha and Beta emission. Today an early Radium dial has no more radio-luminescence due to radiation damage to the phosphor (usually silver activated ZnS). But a dial with a good coating of old luminous paint (see below) can be brought to life again by applying a new overlay of ZnS. I asked Ranfft to test this out and he found that non-activated ZnS applied over an old radio-luminous dial did glow even after several hours in the dark when the light-activated phosphorescence would have vanished. He also reported that Luminova was also activated in the same way but with more brightness than the ZnS. Our conclusion is that if you have a radio-luminescent dial in good condition such as this one Then it could be brought to life again to glow all night long by the application of a layer of Luminova paste over the old numbers and hands. Silver activated ZnS paste would also perform well and be nearer to the original. Activated ZnS is available in small quantities from: https://unitednuclear.com/index.php?main_page=product_info&cPath=16_17_69&products_id=218 If you do want to get into this game then buy a cheap (post Fukushima) radiation monitor from one of the Japanese eBay sources. The above dial has a radiation dose rate above the crystal of 40 micro Sv/h. This is ample for a re-luming job.

I got to say a really interesting article for me. I have re-lumed a couple of watches including an old diver style watch that probably was lumed with the dreaded radium paint !!!!!! I will have to be more carful in future.

I began my scientific career with the Radiological Protection Service of the MRC and have been involved in the protection from Ionizing radiation until retirement. Anilv's advice is good. There is increasing evidence (contested by some) that low levels of radiation are beneficial and so, for me, the wearing of an old Radium luminised watch presents no problem. However when removing the luminous paint it is important to avoid flakes and dust. Just keep everything damped down with water or paraffin and rinse well the tools and everything that came into contact with the luminous paint. If you are getting into this frequently buy a cheap radiation monitor from Japan (they have many on sale since Fukushima) and use this to check the tools and workbench afterwards. Disposing of the spoils for the odd watch dial and hands usually means putting it all into the rubbish bin, but it may depend on local regulations. You can do no better than to read David Boettcher's article on this at: http://www.vintagewatchstraps.com/luminous.htm