Radioactivity 3

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Radioactivity 3

• Background radiation

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'Mr. Average UK Background dose
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Background radiation

• There are radioactive substances all around us,
  including in the ground, in the air, in building
  materials and in food.
• Radiation also reaches us from space.
• The radiation from all these sources is called
  background radiation.

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Background Radiation

• Most of the background radiation dose we receive
  in the UK is from natural sources (about half is
  inhaled as radon gas).
• About 15 of our annual dose comes from human
  activities such as X-rays in hospital or at the
  dentist or emissions from nuclear establishments.

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Your Background Radiation Dose

• The radiation dose you get in a year depends on
• where you live (the rock type in your locality),
• your state of health (whether you require
  treatment or investigation in hospital that
  involves ionizing radiation ),
• your diet (salt substitutes contain potassium
  rather than sodium and the percentage of
  potassium that naturally occurs in the
  radioactive form is higher than that of sodium),
• your occupation (do you work in an environment
  that exposes you to nuclear radiation?)

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Experiments

• You need to count the background radiation before
  you perform an experiment.
• The background count can then be deducted from
  the count in your experiment.