P4 : Irradiation and Contamination

Question 1

Radioactive isotopes

Answer 1

Radioactive isotopes decay and emit radiation from their nuclei
Radiation can be ionizing : it can form charged atoms called ions
Ionizing radiation can increase the risk of cancer in humans

Question 2

Irradiation

Answer 2

Irradiation is exposing an object to nuclear radiation (alpha, beta, gamma or neutrons)
The object does not become radioactive because the object comes in contact with the radiation but not the radioactive isotope itself

Question 3

Precautions

Answer 3

Gloves can be used to protect against alpha radiation
Beta and Gamma radiation can be reduced using a lead apron
Using a lead-glass screen and lead walls

Question 4

Monitoring

Answer 4

With a radiation monitor, we can measure how much radiation has been received
If the person has received too much radiation, we can stop them from working with radioactive isotopes

Question 5

Radioactive Contamination

Answer 5

When unwanted radioactive isotopes end up on other materials, this is called contamination
This is hazardous as the radioactive atoms decay and emit ionizing radiation
With radioactive contamination, you have the radioactive source on you or in you and could inhibit a large dose of radiation

Question 6

Alpha Radiation contamination

Answer 6

Strongly ionizing but easily stopped by dead cells on the skins surface. Alpha emitters can be dangerous if inhaled or swallowed

Question 7

Beta radiation contamination

Answer 7

Quite ionizing, and can penetrate skin into the body

Question 8

Gamma radiation contamination

Answer 8

Weakly ionizing, Can penetrate body but likely to pass straight through

Question 9

Peer review

Answer 9

Over the years scientists have explored the effects of radiation on humans
It is really important that these studies are published then shared with other scientists
This allows the findings to be checked (peer review)