RADIATION – A few points

The low levels of radiation you are exposed to during medical tests can be measured in units called millisieverts (mSv).

Some examples of different levels of radiation are:

A single chest X-ray (0.02 mSv) – This is equivalent to the amount of radiation you would be exposed to during a return flight from London to Spain (the higher up in the atmosphere you are, the less protection you have against cosmic rays).

Natural radiation (2.2 mSv) – The average annual dose that a person in the UK receives from natural sources.

A mammogram (2 to 5 mSv) – The amount of radiation that a woman receives after having a mammogram .

Equivalent to having between 100 and 250 X- Rays, at the same time.

The benefit of detecting breast cancer at an early stage is the dilemma which balances against the risk of any problems from the radiation exposure.

A computerised tomography (CT) scan of the chest, abdomen and pelvis (10 mSv) – The amount of radiation a person receives from a CT scan.

Equivalent to having up to 500 X- Rays, at the same time.

Working with radiation (20 mSv) – The UK legal limit, as set by the Ionising Radiations Regulations (1999), that a classified person who works with radiation may be exposed to in any given year.

However, most workers receive considerably less than this.

This is equivalent to having up to 1,000 X- Rays, over the course of a year, or approx 20 X-Rays per week.