Process of carbon 14 dating
These amounts can vary significantly between samples, ranging up to 1% of the ratio found in living organisms, a concentration comparable to an apparent age of 40,000.), or other unknown secondary sources of carbon-14 production.
The presence of carbon-14 in the isotopic signature of a sample of carbonaceous material possibly indicates its contamination by biogenic sources or the decay of radioactive material in surrounding geologic strata.
Liquid scintillation counting is the preferred method.
These are relatively low energies; the maximum distance traveled is estimated to be 22 cm in air and 0.27 mm in body tissue.
Dating a specific sample of fossilized carbonaceous material is more complicated.
Such deposits often contain trace amounts of carbon-14.
This is small compared to the doses from potassium-40 (0.39 m Sv/year) and radon (variable).
Carbon-14 can be used as a radioactive tracer in medicine. pylori infection, the bacterial urease enzyme breaks down the urea into ammonia and radioactively-labeled carbon dioxide, which can be detected by low-level counting of the patient's breath.