system
Given the following post, respond as if you're commenting on Reddit:
human
How much radiation would you be exposed to holding weapons-grade plutonium in your hand?

In a movie I saw yesterday there were several scenes of the characters holding spheres of weapons-grade plutonium in their bare hands with seemingly no concern for how radioactive it is.

My gut says this is a really, really bad idea, but I'm curious just how bad it would be.  How much radiation would you be dosed with if you did that in real life?
gpt
It depends on how much of it you’re holding, and whether or not criticality is reached. The “common” isotopes of plutonium are radioactive to alpha decay, but Pu always comes cladded in other metals, which the alpha particles can’t penetrate. Some fraction of the time, it will undergo spontaneous fission instead, which will also result in the emission of neutrons and gamma rays. These will in general penetrate through the cladding and give you a dose.

As long as there is no criticality reached, the dose rate won’t be *too* high. People can handle amounts on the order of a few kilograms of weapons-grade plutonium (I personally have done so) without receiving a dangerous dose.

You don’t just hold bare Pu in your bare hands though, the Pu is cladded with some other metal (like zirconium), and you generally wear gloves when handling it. The gloves are not very heavy-duty, as they’re not used to shield radiation. Instead they’re used to mitigate the spread of radioactive contamination. When you’re done handling the material, your hands will generally be tested for contamination, and once you’ve been given the all-clear, you remove the gloves and dispose of them.

So it’s really not as dangerous as you think. The real danger is in criticality accidents, but as long as you’re handling less than the critical mass with your given amount of moderation, then criticality can’t be reached, by definition. A fun fact about it though is that for kilogram amounts of Pu, the cladding actually feels warm to the touch due to the radiation (most of which doesn’t penetrate the cladding).