Having medical scans exposes a person to ionising radiation. The table below shows the average radiation dose for a dental X-ray and a CT scan of the head.
| Examination type | Radiation dose in millisieverts (mSv) |
|---|---|
| Dental X-ray | 0.008 |
| CT scan of the head | 2.0 |
The risk of a scan causing cancer is about 1 in 20,000 for each mSv of radiation received.
Compare the risk of developing cancer from having a CT scan of the head with the risk from having a dental X-ray. Use the data in the table.
16 exam-style questions on AQA GCSE Physics 4.3 Hazards and uses of radioactive emissions and of background radiation, covering 4.3.1 Background radiation, 4.3.2 Different half-lives of radioactive isotopes, and 4.3.3 Uses of nuclear radiation. Each one has a worked solution and a mark scheme showing where the marks go.