Geiger Counter

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I got a Digital Geiger Counter for my birthday (yes, I know, geeky). As a starter use, I measured the background radiation in our house in the East Bay over the past 24 hours. The results appear in the graph below, plotting the "counts per hour" and corresponding μSv/hour over the past 24 hours. The worst-case measured .2 μSv/hour translates to about 1.8 mSv/year, which luckily seems a bit below the worldwide average background dose.


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