A radioactive gas is a gas that contains one or more radionuclides. Radionuclides are atoms that have unstable nuclei, and they emit radiation as they decay. This makes them dangerous to human health, as the radiation can damage cells and cause cancer.
There are many different types of radioactive gas, depending on the radionuclide present. The most common type is radon, which is produced when uranium decays. Other types include krypton-85 and xenon-133, which are used in medical imaging, and carbon-14, which is used in radiocarbon dating.
Radioactive gases can be found in both natural and man-made environments. They may be released into the air from nuclear power plants or uranium mines, for example. Radioactive gases can also be created artificially, such as during nuclear weapons testing.
The level of risk posed by a particular radioactive gas depends on its concentration in the air, how long you are exposed to it for, and your distance from the source. For example, radon levels in indoor air tend to be much higher than outdoors, so you are at greater risk if you spend most of your time indoors. Similarly, if you live near a nuclear power plant or uranium mine, you may be exposed to higher levels of radioactivity than someone who lives further away.