Background Radiation and Contamination Flashcards
(16 cards)
give examples of natural background radiation
- Cosmic (Sun)
- Ground / rocks
- Air - Radon
examples of radiation due to human activity:
- Nuclear explosions
- nuclear waste
- medical
what is background radiation and is it dangerous
- low-level radiation given off by natural and artificial sources all around us
- it is of low enough level that risk of cancer and other complication are negligible
what is irradiation
- objects near a radioactive source - are exposed
- is not radioactive itself
what are way of reducing irradiation
- keeping sources in lead-lined boxes
- standing behind barriers or being in a different room
- using remote controlled arms
what is contamination
when unwanted radioactive atoms get onto or into an object
why is contamination especially dangerous
- these contaminated atoms might decay - releasing radiation, causing you harm
- very dangerous inside the body
what precautions can be taken for contamination
- glove and tongs when handling sources
- aviod particles getting stuck to skin or under nails
- protective suits to stop them breathing in particles - industrial workers
what is the most dangerous types of radiation for irradiation
- beta
- gamma
- can penetrate to organs
- alpha wont be able to penetrate skin
what is radiation measured in
Sieverts , 1Sv = 1000mSv
what type of radiation is most dangerous outside of the body
gamma
beta
why are gamma and beta dangerous outside the body
can penetrate the body and get to delicate organs
why is alpha less dangerous outside of the body
- can’t penetrate the skin
- easily blocked by small air gap
why is alpha very dangerous inside the body
- do all the damage in a very localised area
- highly ionising and cannot penetrate far, so it trapped within the body
why is beta not that dangerous inside the body
- radiation is absorbed over a wider area
- some pass out of the body altogether
why is gamma the least dangerous inside the body
pass straight out - lowest ionising power
