> I'm more scared of alpha than gamma. If the alpha source gets tampered with and becomes a dust somehow, it could stay in someone's lungs, and kill someone wit

> I'm more scared of alpha than gamma. If the alpha source gets tampered with and becomes a dust somehow, it could stay in someone's lungs, and kill someone without being easily detectable. It's not an either/or sort of thing. Gamma decay occurs after alpha or beta decay, so a gamma source will also emit alpha or beta radiation. In the case of Cs-137, it emits a lot of beta radiation. Normally this is shielded, but normally it doesn't fall off a truck..