Background radiation

Background radiation is around us all of the time. It comes from:
- natural sources such as rocks and cosmic rays from space
- man-made sources such as the fallout from nuclear weapons testing and nuclear accidents.

The level of background radiation and radiation dose may be affected by occupation and/or location.

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Radiation dose is measured in sieverts (Sv)

1000 millisieverts (mSv) = 1 sievert (Sv)

Students will not need to recall the unit of radiation dose.

Different half-lives of radioactive isotopes

Radioactive isotopes have a very wide range of half-life values.

Students should be able to explain why the hazards associated with radioactive material differ according to the half-life involved.

Uses of nuclear radiation

Nuclear radiations are used in medicine for the:
- exploration of internal organs
- control or destruction of unwanted tissue.

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Students should be able to:
- describe and evaluate the uses of nuclear radiations for exploration of internal organs, and for control or destruction of unwanted tissue
- evaluate the perceived risks of using nuclear radiations in relation to given data and consequences.