background radiation

• how does background radiation occur?


  natural = natural minerals, radon gas, cosmic radiation from space, c-14/ wood beta decay

  man made = nuclear weapons, nuclear accidents, nuclear energy fallouts, mining bringing radioactive minerals to the surface.
• you should subract the background radiation to avoid systematic errors
• where does background radiation originate from?

  1. naturally occurring unstable isotopes - air, food, rocks, building materials
  2. radiation from space - cosmic rays from the sun however we are protected by earths atmosphere
  3. human activity - nuclear explosions, nuclear waste.
• the risk of harm from a radiation dose is measured in sieverts or millisieverts
• objects near a radioactive source are irradiated by it, but this does not mean that it is radioactive.