What would extreme radiation do to the body?

Radiation question... How much radiation can a body handle without death/sickness?

• -Total body exposure of 100 roentgens causes radiation sickness. -Total body exposure of 400 roentgens causes radiation sickness and death in half the individuals. -100,000 rads causes almost immediate unconsciousness and death within an hour These are the number I found, but, what is the ammount of time for exposure. Is it 100 rotegens over a life time or a closed amount of time?

• Answer:

  More than 50 Sv (>5,000 REM) A worker receiving 100 Sv (10,000 REM) in an accident at Wood River, Rhode Island, USA on 24 July 1964 survived for 49 hours after exposure, and an operator receiving between 60 and 180 Sv (18,000 REM) to his upper body in an accident at Los Alamos, New Mexico, USA on 30 December 1958 survived for 36 hours; details of this accident can be found on page 16 (page 30 in the PDF version) of Los Alamos' 2000 Review of Criticality Accidents [9].