Comment What is safe? (Score 1) 200
You are right. The ignorance of many people on the subject of radioactivity is amazing. I don't know why, maybe because nuclear seems magical. But the radiation produced by an isotope is inversely proportional to the half life. People complain about nuclear waste that will be radioactive for a million years. Sure but that stuff is pretty safe because of that long half life it doesn't produce much radiation. It's the short lived isotopes that are really dangerous because of the amount of radiation they put out. Luckily you don't have to keep them long until they decay to safe levels. It's the stuff right in the middle with half lives in the 10-100 year range. They are radioactive enough to be a health concern but also take a long enough time to decay. Of course the type and energy level of the radiation needs to be factored in as well.