Radiation

• What is background radiation?

  Low-level radiation present all the time
• What are the main sources of background radiation?

  Natural isotopes, cosmic rays, human activity
• What is the absorbed radiation dose?

  Amount of radiation energy absorbed by body
• What does irradiation mean?

  Exposure of objects to radiation
• How can irradiation effects be reduced?

  Using lead-lined boxes and barriers
• What happens if radioactive atoms contaminate an object?

  The object is said to be contaminated
• Why is contamination particularly dangerous?

  Radioactive particles can enter the body
• What is the difference between irradiation and contamination?

  Irradiation is exposure; contamination is presence
• How does radiation damage cells?

  By ionising atoms and molecules within them
• What can lower doses of radiation cause?

  Minor damage leading to mutant cells
• What happens with higher doses of radiation?

  They can kill cells completely
• Which types of radiation are most dangerous outside the body?

  Beta and gamma radiation
• Why is alpha radiation more dangerous inside the body?

  It is strongly ionising and localised
• What are the methods to prevent irradiation and contamination?

  • Use lead-lined boxes for sources
  • Stand behind barriers
  • Use remote-controlled arms
  • Wear protective gear like gloves
• What is the relationship between half-life and safety of radioactive sources?

  Lower activity means safer to be around
• Why is a source with a longer half-life more dangerous over time?

  It retains activity longer than short half-life sources
• What is important when choosing a radioactive source for an application?

  Balance activity level and duration of danger
• What type of radiation is used in household fire alarms?

  Alpha radiation
• How does a smoke detector work?

  Alpha radiation ionises air, creating current
• What is the purpose of irradiating food with gamma rays?

  To kill microbes and prolong shelf life
• Why is gamma radiation preferred for sterilising medical equipment?

  It sterilises without high temperatures
• What type of radiation is used in medical tracers?

  Beta or gamma emitters
• Why must medical tracers have a short half-life?

  To ensure radioactivity quickly disappears
• How is beta radiation used in thickness control?

  It detects changes in material thickness
• Why is a beta source used for thickness measurement?

  It allows partial blockage of radiation
• What are the uses of radiation in various fields?

  • Household fire alarms use alpha radiation
  • Food and equipment sterilisation uses gamma rays
  • Medical tracers use beta or gamma emitters
  • Thickness gauges use beta radiation
• What is the main concern when working with alpha sources?

  Contamination rather than irradiation
• What is the effect of high activity radioactive sources?

  They are more dangerous to be around
• What is the purpose of using protective suits in industrial settings?

  To prevent inhalation of radioactive particles
• Why is it important to monitor radiation exposure for medical staff?

  To ensure their safety from harmful doses
• How does the Earth's atmosphere protect us from cosmic rays?

  It absorbs much of the incoming radiation
• What happens to the activity of a radioactive source over time?

  It decreases as the source decays
• What is the significance of using strong gamma emitters for sterilisation?

  They ensure effective sterilisation over time
• How does the choice of radioactive source affect its application?

  It determines safety and effectiveness in use