You can find some affordable Geiger counters in Amazon. They are accurate, there are a lot of videos in YouTube with comparisons between expensive and well constructed ones with chinese cheap ones and the measurements are equivalents.
Actually it is mine since (maybe) 2002? It was a gift from my girlfriend (we weren’t married yet) and it has ben into a box for several years. A few weeks ago I took it, cleaned it, bought a new battery and a new strap to replace the original, which was damaged. And now I am wearing it again!
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I wrote to the official Citizen service in Spain, my country, and this is what they answered me (in case it helps): "We can assure you that Citizen has not sold and does not sell products with radioactivity. For many years some model has been called "radioactive", specifically the NY0040 series, because in the 70s a material was used for the luminous of the indices and needles in watches that had a material with a tiny amount of a material that people associated with a "radioactive" product, but it is a name given to fans, not because the watch was radioactive as such. If you put in an internet search engine "Radioactive Citizen" you will find that it is a popular name of an old diver.
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