The measure for radiation is in sieverts (SV), more commonly micro (mSV)or millisieverts (uSV.) A fatal dose of radiation is 8 SV. There is a 50% survival rate for those who receive a dose of 4 SV. The type of radiation, proximity to the source, and length of exposure relate to the amount of radiation. Each part of the body is affected differently at different amounts of radiation.
When Secretary McCord see her son in the hospital chapel, she asks him "I thought religion was the opiate of the masses?" This is a paraphrasing of the quote from Karl Marx's A Contribution to the Critique of Hegel's Philosophy of Right.