Radioactivity Safety Flashcards
What happens when alpha beta and gamma radiation enters living cells?
They collide with molecules
What is the problem with these collisions?
They cause ionisation which damages or destroys the molecules
What does lower doses do?
Cause minor damage without killing the cells
What do the collisions with lower doses sometimes cause?
Mutant cells which divide uncontrollably (cancer)
What do higher doses tend to do?
Kill cells completely which causes radiation sickness (a lot of body cells killed at once)
What does the extent of the harmful effects depend on?
How much exposure you have to the radiation
The energy and penetration of the radiation since some types are more hazardous than others
Which sources of radiation are most dangerous outside the body and why?
Beta and gamma because they can get inside delicate organs whereas alpha can’t penetrate skin
Which source of radiation is most dangerous inside the body?
Alpha because they do all their damage in a very localised area
Beta and gamma mostly pass straight out the body without doing much damage
What are three precautions that should be taken when handling radioactive substances?
When conducting experiments use radioactive sources for as short a time as possible to minimise exposure
Never allow skin contact with source (use tongs)
Keep the source pointing away from the body and avoid looking directly at it
What will holding the source at arms length do?
Decrease the amount of radiation that hits you (particularly for alpha that doesn’t travel far in air)
Why is storing the radioactive sources in a lead box a good precaution to take?
All three types of radiation is absorbed by lead
What happens when someone needs radiotherapy?
Only the area of the body that needs to be treated is exposed to radiation the rest is protected with lead
