Good morning everyone, First of all I have to say that I didn't know where to ask this question, but I am sure people with knowledge in nuclear physhics is who I will trust, and not optics amateurs, at least with something potentially dangerous. I got an optics device that has an orange stick of around 20x15mm, with the label "T 0.5Ci" with the radioactivity symbol. I have been studying and it is a ZRAK sight built around 1970-1990 in USSR/Yugoslavia, probably used in some european war. Also, I have read that the radioactive material used to be tritium. Am I in danger by preserving this device? How dangerous is the tritium? Is it possible to be radiating us by just touching the sight or being really close to it? Does this radiation "infect" other materials (like the metal cover) and then those materials "infect" us? In case is dangerous, am I safe if I hide it in a box and cover it with some lead sheet (not hermetic) to avoid it "infects" other objects and tools in the room? - I would preserve and use this sight just if I am not on risk. Radioactivity scares me. Sorry for my ignorance. I have no idea about the behaviour of the tritium or radioactive materials. Also, I give an image from some sight to show how is the metal cover and the symbol, although the image that I attach has another label. Mine is "T 0.5Ci". Regards, Juan.