If you ever wondered why nuclear tests are now performed underground, this is why.Most radiocarbon dating today is done using an accelerator mass spectrometer, an instrument that directly counts the numbers of carbon-14 and carbon-12 in a sample.
But when gas exchange is stopped, be it in a particular part of the body like in deposits in bones and teeth, or when the entire organism dies, the ratio of carbon-14 to carbon-12 begins to decrease.This new method was based on gas and liquid scintillation counting and these methods are still used today, having been demonstrated as more accurate than Libby's original method (3).Willard Libby would receive a Nobel Prize for Chemistry in 1960.A detailed description of radiocarbon dating is available at the Wikipedia radiocarbon dating web page.
Bottom line: Radiocarbon dating is a technique used by scientists to learn the ages of biological specimens from the distant past.
The method developed in the 1940's and was a ground-breaking piece of research that would change dating methods forever. Libby calculated the rate of radioactive decay of the C isotope (4) in carbon black powder.