For all those people in California and the rest of the United States who are worried about radiation from Japan, I made this simple chart. It shows how radiation from Fukushima scales to other sources of radiation. The important thing to note is that everyone gets 3650 microSievert per year from natural sources. You can't escape that. This amount is 36,500 time greater than what a Californian might see from Japan. Put away your potassium iodide pills.