Radiation

It’s often said that radiation is natural, and that we are exposed to increased radiation just by flying in airplanes and sitting in the dentists chair.  To put these sorts of statements into perspective, the Guardian newspaper created this table explaining effects of various levels of radiation damage, expressed in millisieverts.

Event Radiation reading, millisievert (mSv)
Single dose, fatal within weeks 10,000
Typical dosage recorded in those Chernobyl workers who died within a month 6,000
Single dose which would kill half of those exposed to it within a month 5,000
Single dose which would cause radiation sickness, including nausea, lower white blood cell count. Not fatal 1,000
Accumulated dosage estimated to cause a fatal cancer many years later in 5% of people 1,000
Max radiation levels recorded at Fukushima plant (Oct. 2015), per hour 400
Exposure of Chernobyl residents who were relocated after the blast in 1986 350
Recommended limit for radiation workers every five years 100
Lowest annual dose at which any increase in cancer is clearly evident 100
CT scan: heart 16
CT scan: abdomen & pelvis 15
Dose in full-body CT scan 10
Airline crew flying New York to Tokyo polar route, annual exposure 9
Natural radiation we’re all exposed to, per year 2
CT scan: head 2
Spine x-ray 1.5
Radiation per hour detected at Fukushimia site, 12 March 1.015
Mammogram breast x-ray 0.4
Chest x-ray 0.1
Dental x-ray 0.005