Background Radiation and Contamination Flashcards
What is background radiation?
The low-level radiation that is around us all the time
Describe the origins of background radiation.
Sources that background radiation comes from include:
- Radioactivity of naturally occurring unstable isotopes which are all around us
- Radiation from space
- Radiation due to human activity
(Exam-style question)
Any three from:
- Rocks
- Cosmic rays
- Nuclear waste
- Nuclear power stations
- Buildings
- Food
- Radon
- Sun
- Medical / X-rays
Explain the difference between contamination and irradiation.
- Contamination is when unwanted radioactive particles get onto an object
- Irradiation is when an object is exposed to radiation
(Exam-style question)
A scientist is using a low activity radioactive sample.
Give one example of how they can protect themself from irradiation and one example of how they can protect themself from contamination.
For irradiation:
- Use shielding / stand behind barriers
- Work in a different room to the source
- Store sample in lead-lined box
For contamination:
- Wear gloves
- Handle source with tongs
- Wear protective suit or mask
What causes tissue damage?
Ionising radiation that damages cells
(Exam-style question)
Explain what can happen to the body if a person has a prolonged exposure to gamma rays.
- Because gamma rays are ionising, they cause damage to cells
- This can give rise to mutations which can lead to cancer
What is the effect of a high dose of ionising radiation?
It kills cells completely, causing radiation sickness
