Bismuth-214 (Bi-214) is a radioactive isotope of bismuth with a half-life of approximately 19.9 minutes. It is part of the uranium-238 decay series, formed as a decay product of radon-222 through polonium-218 and lead-214. Bi-214 decays primarily via beta emission to polonium-214, accompanied by strong gamma radiation at characteristic energies, making it highly detectable using gamma spectrometry.

This isotope is almost always present in a mixture with other isotopes characteristic of the decay chain of uranium, radium or radon.

Bi-214 is widely used in environmental monitoring and radiation detection calibration due to its strong gamma emissions. In research, Bi-214 is studied to understand decay chains and natural radiation distribution. It also plays a role in validating radiation models and monitoring radon progeny in indoor air quality studies.

Bi-214 is naturally found as part of the uranium-238 decay chain and is present in trace amounts in environments with uranium-bearing minerals, such as uraninite and pitchblende. It is commonly encountered in soils, rocks, and groundwater in areas with high uranium content. Bi-214 is also found in the atmosphere as a decay product of radon-222, contributing to natural background radiation. Its strong gamma emissions make it a critical component in environmental radiation monitoring and uranium exploration.

Bi-214

Bismuth-214
Natural α, β, γ radiation

Half-life: 19.9 min Main emission lines: 609, 1120, 1760 keV Decay chain: Ra-226 Related lines: 47, 78, 186, 242, 295, 351, 2200 keV