Radiation safety and personal survival depend on three concepts:
1. Time -- The length of time you are exposed to the radiation
2. Distance -- How far you can get from the radiation source
3. Shielding -- any solid object you can put between you and the source of radiation.
Because I am an old phart and do not see the use of the new units (SI) used to describe radiation when they are harder to remember and don't add anything to your safety, I will use the unit Radiation Absorbed Dose (RAD). All those other sieverts, greys, etc were established to entice all the countries of the "civilized" world to participate in the new SI system, designed to restrain trade from the US.
The international entities and the US Nuclear Regulatory Commission (NRC) have established radiation exposure limits for PEACETIME radiation exposure. They are based on the genetic pool background exposure concentrated and divided amoung radiation workers. Those limits are (but not limited to):
2mr in any one hour
100 mr in any one week
1250 mr in any one quarter
5000 mr (5R) per year
total of 5R for each year over the age of 18
Because this was once based on the gene pool, womyn and minors were restricted to 1/10 of the allowed dose. However, since womyn's lib, they takes the same chance as the rest of us.
NOW FORGET ALL THAT STUFF -- THIS IS WAR. OR SOME
HAS DECIDED TO DO IN THE GREAT SATAN
Here is what you gotta know:
25R An experienced blood chemist can begin to detect changes in blood.
100R Some folks are going to start to get sick.
200R Half of those exposed will get sick.
400R Everyone gets sick, half die.
600R Almost every one dies.
1000R Believe it or not, there are a small number still around.
Don't count on any of them being you.