Subduction Zone
Veteran Member
The container was so deadly that you might live if you did so, when this was new. Co 60 has about a five year half life. That particular sample would be almost 60 years old right now. That is twelve half lives. So (1/4000) of the original radioactivity. It would not be the almost instant death that it was back then. I would still not put it under my pillow.
A bit more discussion follow here:
Why does Cobalt-60 have Danger Drop & Run printed on its storage capsule?
Answer (1 of 2): Two comments. First, not all Cobalt-60 sources are labeled such. There have been radioactive sources manufactured in the past with this labeling, below is a photo of one. Notice that the activity of that source is listed as “3540 Curies 7–1–63”. At the time of manufacture, the d...
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