Скачать или смотреть Victoreen CDV700-6B Geiger Counter Check Source Rad Survey

Brought a calibrated radiation survey meter home from work (Thanks GE Healthcare) to perform a measurement on the amount of gamma radiation (x-rays) given off by the check source on my old CD Geiger counter (CDV700-6B).

Measured ~1.4 mRem/h, directly at the source.
At a distance of ~6 inches, 0.04 mRem/h was measured.

Now if the check source is U-238 as most people assume, then a majority of the radioactivity is alpha and beta decay, which this meter will not measure. The good news is that this form of radiation is absorbed by your clothing, or the surface layer of your skin and poses much less of an external risk as opposed to gamma rays.

So these units are plenty safe to own and operate, but I would not sleep right next to it.