7.5 - Radioactive Decay & Half-Life
Background radiation and correcting the count rate
Background radiation is the low-level ionising radiation that's around us all the time.
Natural sources
- Radon gas and radioactive elements in rocks, soil, air, food and building materials.
- Cosmic rays - Radiation reaching Earth from space.
Man-made sources
- Fallout from nuclear weapons testing.
- Medical uses (e.g. X-rays), nuclear power accidents, and radioactive waste.
Correcting for background radiation
- Measure the background count rate with no source present.
- Measure the count rate with the source in place.
- Subtract the background count rate to get the corrected count rate from the source alone.
TermDefinition
Background radiationThe low-level ionising radiation that is around us all the time.