A lot has been said over the years about Radium and its ill effects, and how it relates to horology. Watchmakers typically have had to contend with a vast array of toxic materials, Cyanide, Trichlorethylene, Carbon Tetrachloride, Ammoniated cleaning solutions, both water and hydrocarbon based, Rouges and polishing mediums, and of course, Radium.
I recently had the opportunity to use a Geiger counter on a variety of test subjects, and the results have surprised me.
First I tested a tiny ladies watch, no bigger than a dime, and it topped out at 12.2 microsieverts per hour. This seems to be a kind of average for a lot of non-military watches, and depends, of course, on the amount of Radium appluied to the dial. After being stripped of Radium, the dial still remains hot, as does the movt.
I tested my 1952 Rolex and it kicked out 21.3 microsieverts per hour, which was very high, considering it had been stripped and re-lumed.
I tested a car clock I had stripped in school, and it still kicked out 18.5 ms/hr.
An RAF pocket watch bomb timer put out over 30 ms/hr. and that was just from one hand.
I recently checked a very thin hand from a Universal handwind from the early 60's and it put out a whopping 52 ms/h.
For comparison, where I live, background radiation is .1 to .2 microsieverts per hour.
Elsewhere we have covered this quite well, but I will include a few of the facts here. Radium's most stable isotope, used in horology, has a half life of 1601 years. It doesn't glow after awhile because the Zinc Sulfide has degraded. Adding Zinc Sulfide does not make it glow again, as I had theorized earlier. The body sees Radium as Calcium, and imports it into the bones, leaving the exposed person with the terrible ache of Radium sickness, that sometimes doesn't show symptoms for years. The Alpha particles exit the watch case through the front, and very little, if any, goes out the back, being blocked by the dial and movt. I checked quite a few watches for this.
The dose is small, and concentrated to a small area. Full body doses are of course, more toxic, and standards are based on this.
After much thought on the matter, I decided a few years ago to not ever strip Radium from dials or hands ever again, and I believe this is a good idea. Contamination is almost assured, and ingestion of any particles could cause some serious health issues.
Additionally, I plan to take this up with my Doctor and radiologist at some point, and see what they think.