These are important radiation doses to commit to memory, you can measure your accumulated dose by the use of a radiation dosimeter.
-Max yearly dose for radiation workers set by the EPA - 50 mSv or 5 rad/rem
-Cancer threshold dose = 100 mSv or 10 rad/rem also the dose limit for emergency workers protecting critical property
-Max dose for emergency workers engaged in life saving work = 250 mSV or 25 rad/rem
-Radiation sickness begins = 400 mSv or 40 rad/rem
-Severe radiation sickness = 2 SV/2,000mSv or 200 rad/rem
-Severe radiation sickness possible survival with immediate medical attention = 4 SV/4,000 mSv or 400 rad/rem
-Fatal radiation dose, death certain even with treatment = 8 SV/8,000mSv or 800 rad/rem