I have the GMC 500+. I see that it reads to 42,500 uSv/hr is that equal to 4.25 Rem/hr? The little card that came with it shows >13 uSv/h is extremely high. I am only interested for emergency. What is the measurement I need? I know 500-600 R/hr you will die soon.100-200 R/hr you will be sick and could die. I can not find any You Tube or information on this measurement with CPM - uSv/h for fall out doses.