Röntgen: Meaning (information, definition, explanation, facts)

The röntgen (symbol R) is a unit of dosage of X-rays or gamma radiation, being the dose that liberates positive and negative charges of 2.58×10^-4 coulombs per kilogram of air. It is named after the physicist Wilhelm Röntgen.

Natural background is around 10 μR per hour. 500 R in 5 h is lethal for humans.