[Tuna-Fish]

If they fully knew the risks, they would have probably used the device to warm up themselves. The plutonium-238 used in the SNAP devices is notable for not having any significant decay modes other than alpha. So long as the device remains intact, a sheet of paper is sufficient for radiation shielding.

[hga]

I've always read the outer layers of your skin are sufficient; just avoid ingestion or inhalation and you're fine.

This is a very sloppy and/or fear mongering article, e.g. when it talks about the device being 1/2 the size of the Hiroshima bomb, which was a uranium gun assembly design. It never points out you can't make this isotope of plutonium go boom, or the much fuzzier probability that a breach of the containment wouldn't likely cause a widespread contamination problem.